The matrix M is given by M = ( (1/2) (-√3/2) / (√3/2) (1/2) ) ( (14) (0) / (0) (1) )
- (a)The matrix M represents a sequence of two geometrical transformations in the x-y plane. Give full details of each transformation, and make clear the order in which they are applied.[4]
- (b)Write M⁻¹ as the product of two matrices, neither of which is I.[2]
- (c)Find the equations of the invariant lines, through the origin, of the transformation represented by M.[5]
- (d)The triangle ABC in the x-y plane is transformed by M onto triangle DEF. Given that the area of triangle DEF is 28 cm², find the area of triangle ABC.[2]
Mark scheme
Marking points from the official mark scheme (May/June 2024). The mark or mark type is shown in brackets.
- [B1] [One way] stretch, rotation
- [B1] Stretch followed by rotation
- [B1] Stretch parallel to the x-axis, scale factor 14
- [B1] Rotation, π/3 [anticlockwise] about the origin.
- [B1] Both inverses correct.
- [B1] Correct order.
- [B1] M = ( (7) (-√3) / (7√3) (1/2) )
- [B1] Transforms (x / y) to (X / Y)
- [M1] Uses y = mx and Y = mX .
- [A1]
- [A1]
- [M1] Uses |DEF| = | det M|| ABC| .
- [A1] 2 cm² Allow with units missing.
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →