A problem by Prabhakar Kumar
Level
pending
here's a cool trigonometry question
9sinx+40cosx=41
find cosx
0.975
0.4
0.6
0.5
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1 solution
sinx=(1-cos^2 x )^0.5 1- 9(1-cos^2 x)^0.5 +40cosx=41 2- 81(1-cos^2 x ) + 1600 cos^2 x = 1681 3- 1519cos^2 x =1600 4- cosx= 0.9743