Question

if the axes are rotated the an angle π/2 in the positive direction, the new coordinatesof (x,y) are​

Answer 1

if the axes are rotated about an angle π/2 in the positive direction, the new coordinates of (x,y) are reversed with negative sign on x , x will become y, y will become - x.

I guess this is the answer..

If we rotate axes by an angle $\theta$, ( x , y) becomes $( xcos\theta + ysin\theta , -xsin \theta+ ycos \theta )$

Put $\theta = \frac{\pi}{2}$, get your answer.

Good night.

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