1991 AHSME Problems/Problem 24
Problem
The graph, of is rotated counter-clockwise about the origin to obtain a new graph . Which of the following is an equation for ?
(A) (B) (C) (D) (E)
Solution
Rotating a point anticlockwise about the origin maps it to (You can prove this geometrically, or using matrices if you aren't convinced). Thus maps to , so new old , so the new equation is
See also
1991 AHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 23 |
Followed by Problem 25 | |
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