Let S1 and S2 be the matrices of the symmetry with respect to the vectors [ 1 0] and [1 1] respectively. Compute S1S2. What kind of linear transformation is S1 S2? Solution In general, shears are transformation in the plane with the property that there is a vector s1 such that T(s1) = s1w and T(s2) =s2 is a multiple of s1 for all s2 Shear transformations are invertible, [ 1 0 ] . [1 1] = 1.