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:
906
Step-by-step explanation:
First solve it, then do the reverse operation to it
area = length times width, so length = area / width
5 1/5 mi^2 5.2 mi^2
Here, length = ------------------- = --------------- = 2.66666... mi = 2 2/3 mi (answer)
1 19/20 mi 1.95 mi
