Geometrical Applications
       of Differentiation
The First Derivative
Geometrical Applications
       of Differentiation            d              dy
The First Derivative y, f  x ,       f  x ,
                                     dx             dx
Geometrical Applications
       of Differentiation        d              dy
The First Derivative y, f  x ,   f  x ,
                                 dx             dx
  dy
     measures the slope of the tangent to a curve
  dx
Geometrical Applications
       of Differentiation            d             dy
The First Derivative y, f  x ,      f  x ,
                                    dx             dx
  dy
     measures the slope of the tangent to a curve
  dx
               If f  x   0, the curve is increasing
Geometrical Applications
       of Differentiation            d              dy
The First Derivative y, f  x ,       f  x ,
                                     dx             dx
  dy
     measures the slope of the tangent to a curve
  dx
               If f  x   0, the curve is increasing
               If f  x   0, the curve is decreasing
Geometrical Applications
       of Differentiation            d              dy
The First Derivative y, f  x ,       f  x ,
                                     dx             dx
  dy
     measures the slope of the tangent to a curve
  dx
               If f  x   0, the curve is increasing
               If f  x   0, the curve is decreasing
               If f  x   0, the curve is stationary
Geometrical Applications
       of Differentiation            d              dy
The First Derivative y, f  x ,       f  x ,
                                     dx             dx
  dy
     measures the slope of the tangent to a curve
  dx
               If f  x   0, the curve is increasing
               If f  x   0, the curve is decreasing
               If f  x   0, the curve is stationary
 e.g. For the curve y  3 x 2  x 3 , find all of the stationary points
      and determine their nature.
      Hence sketch the curve
Geometrical Applications
       of Differentiation            d              dy
The First Derivative y, f  x ,       f  x ,
                                     dx             dx
  dy
     measures the slope of the tangent to a curve
  dx
               If f  x   0, the curve is increasing
               If f  x   0, the curve is decreasing
               If f  x   0, the curve is stationary
 e.g. For the curve y  3 x 2  x 3 , find all of the stationary points
      and determine their nature.
      Hence sketch the curve
                                     dy
                                          6 x  3x 2
                                     dx
dy
Stationary points occur when  0
                            dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
              2
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
   x  0 or x  2
dy
  Stationary points occur when  0
                                 dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
   x  0 or x  2
  stationary points occur at 0,0  and 2,4 
dy
  Stationary points occur when  0
                                 dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
   x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
         x
        dy
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
         x             0
        dy
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
         x             0
        dy             0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
         x      0     0
        dy             0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
         x      0     0     0
        dy             0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0
        dy              0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0
        dy     (-9)
                        0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
         x
        dy
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
         x              2
        dy
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
         x              2
        dy              0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
         x      2      2
        dy              0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
         x      2      2    2
        dy              0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
                 
         x      2(1)    2    2
        dy              0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
                 
         x      2(1)    2    2
        dy     (3)
                        0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
                 
         x      2(1)    2    2 (3)
        dy     (3)
                        0
        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
                 
         x      2(1)    2    2 (3)
        dy     (3)
                        0     (-9)


        dx
dy
  Stationary points occur when  0
                              dx
i.e. 6 x  3 x  0
               2


     3 x 2  x   0
  x  0 or x  2
  stationary points occur at 0,0  and 2,4 
0,0
                 
         x      0(-1)   0    0 (1)
        dy     (-9)
                        0     (3)


        dx                               0,0  is a minimum turning point
2,4
                 
         x      2(1)    2    2 (3)
        dy     (3)
                        0     (-9)


        dx                              2,4  is a maximum turning point
y




    x
y




    x
y

    2,4




            x
y

    2,4




                        x




            y  3x 2  x 3
Exercise 10A; 1, 2ace, 4, 5, 6ac, 7, 8, 9ace etc,
           11, 12, 13, 15ace, 16, 17

Exercise 10B; 1ad, 2ac, 3ac, 5, 6, 7ac, 8, 10, 12

11X1 T09 01 first derivative

  • 1.
    Geometrical Applications of Differentiation The First Derivative
  • 2.
    Geometrical Applications of Differentiation d dy The First Derivative y, f  x ,  f  x , dx dx
  • 3.
    Geometrical Applications of Differentiation d dy The First Derivative y, f  x ,  f  x , dx dx dy measures the slope of the tangent to a curve dx
  • 4.
    Geometrical Applications of Differentiation d dy The First Derivative y, f  x ,  f  x , dx dx dy measures the slope of the tangent to a curve dx If f  x   0, the curve is increasing
  • 5.
    Geometrical Applications of Differentiation d dy The First Derivative y, f  x ,  f  x , dx dx dy measures the slope of the tangent to a curve dx If f  x   0, the curve is increasing If f  x   0, the curve is decreasing
  • 6.
    Geometrical Applications of Differentiation d dy The First Derivative y, f  x ,  f  x , dx dx dy measures the slope of the tangent to a curve dx If f  x   0, the curve is increasing If f  x   0, the curve is decreasing If f  x   0, the curve is stationary
  • 7.
    Geometrical Applications of Differentiation d dy The First Derivative y, f  x ,  f  x , dx dx dy measures the slope of the tangent to a curve dx If f  x   0, the curve is increasing If f  x   0, the curve is decreasing If f  x   0, the curve is stationary e.g. For the curve y  3 x 2  x 3 , find all of the stationary points and determine their nature. Hence sketch the curve
  • 8.
    Geometrical Applications of Differentiation d dy The First Derivative y, f  x ,  f  x , dx dx dy measures the slope of the tangent to a curve dx If f  x   0, the curve is increasing If f  x   0, the curve is decreasing If f  x   0, the curve is stationary e.g. For the curve y  3 x 2  x 3 , find all of the stationary points and determine their nature. Hence sketch the curve dy  6 x  3x 2 dx
  • 9.
  • 10.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2
  • 11.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2
  • 12.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4 
  • 13.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0
  • 14.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0 x dy dx
  • 15.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0 x 0 dy dx
  • 16.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0 x 0 dy 0 dx
  • 17.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0 x 0 0 dy 0 dx
  • 18.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0 x 0 0 0 dy 0 dx
  • 19.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 dy 0 dx
  • 20.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 dy (-9) 0 dx
  • 21.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 dx
  • 22.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx
  • 23.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point
  • 24.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4
  • 25.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4 x dy dx
  • 26.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4 x 2 dy dx
  • 27.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4 x 2 dy 0 dx
  • 28.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4 x 2 2 dy 0 dx
  • 29.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4 x 2 2 2 dy 0 dx
  • 30.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4  x 2(1) 2 2 dy 0 dx
  • 31.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4  x 2(1) 2 2 dy (3) 0 dx
  • 32.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4  x 2(1) 2 2 (3) dy (3) 0 dx
  • 33.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4  x 2(1) 2 2 (3) dy (3) 0 (-9) dx
  • 34.
    dy Stationarypoints occur when  0 dx i.e. 6 x  3 x  0 2 3 x 2  x   0 x  0 or x  2  stationary points occur at 0,0  and 2,4  0,0  x 0(-1) 0 0 (1) dy (-9) 0 (3) dx  0,0  is a minimum turning point 2,4  x 2(1) 2 2 (3) dy (3) 0 (-9) dx  2,4  is a maximum turning point
  • 35.
    y x
  • 36.
    y x
  • 37.
    y 2,4 x
  • 38.
    y 2,4 x y  3x 2  x 3
  • 39.
    Exercise 10A; 1,2ace, 4, 5, 6ac, 7, 8, 9ace etc, 11, 12, 13, 15ace, 16, 17 Exercise 10B; 1ad, 2ac, 3ac, 5, 6, 7ac, 8, 10, 12