Question

Please teach me the steps to solve this problem
Suppose sin Alpha= 4/5, 0 10 years ago

Answer 1

do you remember the double angle identity for sine?
\[\sin(2 \alpha)=2 \sin(\alpha)\cos(\alpha)\]

also draw a right triangle in the appropriate quadrant.

Answer 2

find the adjacent side

Answer 3

you want to find the adjacent side so you find cos(alpha)

Answer 4

25-16=sqr9=3
so 2(4/5)(3/5)?