We know that sin2x=2sinxcosx
(search the net for proof if you wish)
So the original equation becomes
2sinxcosx-sinx=0
The two terms both have sinx that can be taken out to get:
sinx(2cosx-1)=0
This is true if sinx=0 or 2cosx-1=0 , rewritten: cosx=1/2
sinx=0 than x=2kπ
cosx=1/2 than x=π/3+2kπ
where k is an integer
Answer:
$29.41
Step-by-step explanation:
You know the discount price is 25 and the original is unknown so call it x. The sale is 15% off and that means that the jeans are 85% of what they used to be since 100-15 is 85. Then you plug it into a formula of 25/x = 85/100 then you cross multiply to get 2500=85x and when you solve for x and round you get $29.41
