Answer:
Measurement error. Took the quiz and got it right.
Step-by-step explanation:
Answer with Explanation:
Keep in mind these trigonometric Identity:
1. Cos²x - Sin² x= Cos 2 x
2. Cos 2 x = 2 Cos²x-1
3. Cos 2 x = 1 - 2 Sin²x
Now, Coming to the Problem
1 + Cos (18 x)
= 1 + Cos (2 × 9 x)
= 2 Cos ² (9 x)→→→ Cos (2 × 9 x)= 2 Cos² (9 x) - 1
When ever I encounter problem like this, I make the equation become:
z = anything buy z.
First, you want to get 2/5 to the other side, to do so, you need to multiply 5/2 on both side. then you are left with z+1=5/2 y. Then you subtract 1 from both sides to make z on its own. The answer should be z = 3/2y or z= 1
y
2/5(z+1)=y
2/5(z+1)5/2=5/2y
z+1=5/2y
z+1-1=5/2y-1
z=3/2y or z=<span>1
y</span>