tan A = -21/20 90 degrees< A < 180 degrees (meaning in QII) find cos Is it -20?

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Originally Posted by daydreembelievr tan A = -21/20 90 degrees< A < 180 degrees (meaning in QII) find cos Is it -20? Obviously not since (and you should know this) . Hint: .

Originally Posted by daydreembelievr tan A = -21/20 90 degrees< A < 180 degrees (meaning in QII) find cos Is it -20? No remember -1=<sinx=<1 & -1=<cosx=<1 cos is negative in QII so put a (-) sign

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