## anonymous one year ago Please teach me the steps to solve this problem Suppose sin Alpha= 4/5, 0<Alpha<pie/2 and sin beta = 5/13, pie/2<beta<pie Find the exact value of sin 2Alpha sin(alpha-beta)

1. freckles

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. |dw:1436817504152:dw|

2. freckles

3. freckles

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

4. anonymous

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