If A,B, C are acute angles of DABC, then pointegral whose co... | MATH - POINTS RELATE TO TRIANGLE (ORTHOCENTRE,...) | SolveeIt | Solveeit

Today, August 18

Question

If A,B, C are acute angles of DABC, then point whose coordinates are (cos B – sin A, sin B –cos A) can lie in-

A

First and second quadrant

B

Second quadrant only

C

Third and fourth quadrant

D

Second and third quadrant

Answer

Second quadrant only

Explanation

Solution

A + B > $\frac{\pi}{2}$ \ A > $\frac{\pi}{2}$ – B \ sin A > cos B

Also B > $\frac{\pi}{2}$ – A Ž sin B > cos A