When evaluating, you must combine like terms first, so subtract 4 from 1/2 then multiply that number by -7/4, this will give you the value of x.
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:
1 is Answer.
Step-by-step explanation

= 
As we know that ω²+ω+1=0
Thus putting in above equation, we get
= 
Rearranging and simplifying:
= 
= 
= 
= 1 Answer
Step-by-step explanation:
2*5*9*x = 540
x = 540/90 = 54/9 = 6
option D
The answer is 6:15, but if u need to simplify the answer would be 2:5.