If sinθ =4/7, what is cosθ?
3 Answers
Explanation:
Since
you have
So
Jun 20, 2018
Explanation:
We want to find
By the pythagorean trig identity
color(blue)(cos^2(theta)+sin^2(theta)=1
=>cos^2(theta)=1-sin^2(theta)
=>cos(theta)=+-sqrt(1-sin^2(theta))
Substitute
cos(theta)=+-sqrt(1-(4/7)^2)
color(white)(cos(theta))=+-sqrt(1-(16/49)
color(white)(cos(theta))=+-sqrt((49-16)/49)
color(white)(cos(theta))=+-sqrt(33)/7
Jun 20, 2018
Explanation:
Using the relation