If sin (x)= 3/8, where x is in quadrant 2, how would you find cos (x)?
1 Answer
Aug 6, 2017
Explanation:
•color(white)(x)sin^2x+cos^2x=1
rArrcosx=+-sqrt(1-sin^2x)
"x is in the second quadrant hence "cosx<0
cosx=-sqrt(1-(3/8)^2)
color(white)(cosx)=-sqrt(1-9/64)=-sqrt(55/64
color(white)(cosx)=-sqrt55/8