Hi! I am reviewing for my calculus placement test, and in the review book, the one question says:
1. If x is an angle between pi/2 and pi, and sin x =3/5, what is cos x?
note* - x is actually pthata, in my booklet, but I don't have that symbol on my keyboard.
note* - I did find that sin x = cos (pi/2-x) but I don't understand what this means!
Thanks in advance!
1. If x is an angle between pi/2 and pi, and sin x =3/5, what is cos x?
note* - x is actually pthata, in my booklet, but I don't have that symbol on my keyboard.
note* - I did find that sin x = cos (pi/2-x) but I don't understand what this means!
Thanks in advance!
-
You must use formula
sin^2x + cos^2x = 1
or
cos^2x = 1 - sin^2x = 16/25
cosx = +4/5
sin^2x + cos^2x = 1
or
cos^2x = 1 - sin^2x = 16/25
cosx = +4/5
-
the relation between sine and cosine is:
1. sin^2(x)+cos^2(x)=1
1. sin^2(x)+cos^2(x)=1