Question

If sin Tetha= 4/5 then find cos Tetha

Answer 1

Hello friend
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If sin tetha= 4/5
then cos tetha = ??

So,by using the formula

Sin^2 tetha + cos^2tetha = 1

(4/5)^2 + cos^2 tetha = 1

16/25 + cos^2 tetha = 1

cos^2 tetha = 1 - 11/25

cos^2 tetha = 25 - 16/25

cos^2 tetha = 9/25

cos tetha = 3/5........(taking square root)

hence, cos tetha = 3/5

I hope this will helps you..

Thanks..

Answer 2

sin^2 a+cos^2 a=1
(4/5)^2+cos^2 a=1
16/25+cos^2 a=1
cos^2 a=1-16/25
cos^2 a=25-16/25
cos^2 a=9/25
therefore cos theta=3/5