Answer:
<u>-2</u>
Step-by-step explanation:
Solving :


3(x + 2) = 5(2x + 4)
3x + 6 = 10x + 20
10x - 3x = 6 - 20
7x = -14
x = <u>-2</u>
Right side of the equation:
cos ( A - B ) - cos ( A + B ) =
= cos A cos B + sin A sin B - ( cos A cos B - sin A sin B ) =
= cos A cos B + sin A sin B - cos A cos B + sin A sin B =
= 2 sin A sin B - left side of the equation ( correct )
Put the value of x to the inequality:

im sorry i dont understand that brother like thats sum weird