10. The exponent of the highest degree term in a
polynomial is known as its degree.
For Eg. X3 +2x2+4x+5
In this the highest degree is “3”
11. Types of polynomial on the basis of degree are :
Linear polynomial: A polynomial of degree 1 is called a
linear polynomial.
Quadratic polynomial: A polynomial of degree 2 is called
a quadratic polynomial.
Cubic polynomial : A polynomial of degree 3 is called a
cubic polynomial.
Biquadratic polynomial : A polynomial of degree 4 is
called a biquadratic polynomial.
12. Degree Classify by
degree
Classify by
no. of
terms.
5 0 Constant Monomi
al
2x - 4 1 Linear Binomial
3x2 + x 2 Quadrati
c
Binomial
x3 - 4x2 +
1
3 Cubic Polynomial
s
13.
14. Let f(x) be a polynomial of degree n > 1 and let a be any real number.
When f(x) is divided by (x-a) , then the remainder is f(a).
PROOF Suppose when f(x) is divided by (x-a), the quotient is g(x) and the remainder
is r(x).
Then, degree r(x) < degree (x-a)
degree r(x) < 1 [ therefore, degree (x-a)=1]
degree r(x) = 0
r(x) is constant, equal to r (say)
Thus, when f(x) is divided by (x-a), then the quotient is g9x) and the remainder is r.
Therefore, f(x) = (x-a)*g(x) + r (i)
Putting x=a in (i), we get r = f(a)
Thus, when f(x) is divided by (x-a), then the remainder is f(a).
15. Let f(x) be a polynomial of degree n > 1 and let a be
any real number.
(i) If f(a) = 0 then (x-a) is a factor of f(x).
PROOF let f(a) = 0
On dividing f(x) by 9x-a), let g(x) be the quotient.
Also, by remainder theorem, when f(x) is divided
by (x-a), then the remainder is f(a).
therefore f(x) = (x-a)*g(x) + f(a)
f(x) = (x-a)*g(x) [therefore
f(a)=0(given]
(x-a) is a factor of f(x).
16. Some common identities used to factorize polynomials
(a+b)2=a2+b2+2ab (x+a)(x+b)=x2+(a+b)x+ab(a-b)2=a2+b2-2ab a2-b2=(a+b)(a-b)
17. Advanced identities used to factorize polynomials
(x+y+z)2=x2+y2+z2
+2xy+2yz+2zx
(x-y)3=x3-y3-
3xy(x-y)
(x+y)3=x3+y3+
3xy(x+y)
x3+y3=(x+y) *
(x2+y2-xy) x3-y3=(x+y) *
(x2+y2+xy)
18. 1) Polynomials of degree 1, 2 & 3 are called
linear,
quadric and cubic polynomials
respectively.
2) A quadric polynomial can have at most two
zeros and
a cubic polynomial can have three zeros.
3) If we are given with the sum and product
of zeros we can find the polynomial by the
following formula:
K[x2+(sum of zeros)x+(Product of zeros)]
19. 4) If two zeros of a polynomial are given then we can
find the third zero by the following steps:
Convert the zeros into factors of the polynomial
Make a combined factor by multiplying the two
factors
Now divide the polynomial by the combined factor
Write the quotient separately
Do middle term splitting
By this process, we can find the third zero of the
polynomial.
20. A real number ‘a’ is a zero of a polynomial p(x) if p(a)=0.
In this case, a is also called a root of the equation
p(x)=0.
Every linear polynomial in one variable has a unique
zero, a non-zero constant polynomial has no zero, and
every real number is a zero of the zero polynomial.