Answer:
x = π/6, π/2, 5π/6, 3π/2
Step-by-step explanation:
cos x = sin(2x)
Use double angle formula.
cos x = 2 sin x cos x
Move everything to one side and factor.
cos x − 2 sin x cos x = 0
cos x (1 − 2 sin x) = 0
Set each factor to 0 and solve.
cos x = 0
x = π/2, 3π/2
1 − 2 sin x = 0
sin x = 1/2
x = π/6, 5π/6
The total solution is:
x = π/6, π/2, 5π/6, 3π/2
<span>−40+(−20)+(−60)
= -40 - 20 - 60
= -120</span>
7y-8=6y+1
Combine like terms:
7y-8-6y=6y+1-6y
y-8+8=1+8
y=9
Y=9 :)
Answer:
answer is E
Step-by-step explanation:
4 x 12 i= 48
square root of 4=2
12= 4x3
square root of 4 again = 2
2x2 =4
so left with 4 square root 3
Answer: 20
Step-by-step explanation:
27 apples - 7 apples = 20 apples