Using the identity :
Cos (2a) = 1-2 Sin^2(a)
Therefore :<span>1−2 sin ^2 (22.5∘) = Cos(2a)
= Cos (2 * 22.5) = Cos 45</span>
Answer:
50
Step-by-step explanation:
.3x=15
x=50
Answer:
x = 0 and x = 3
Step-by-step explanation:
I will assume that you mean:
4 8
---- + --------- = 4
x x + 2
Here the LCD is x(x + 2).
Multiplying all 3 terms by x(x + 2), we get:
4(x + 2) + 8x = 4(x)(x + 2), or
4x + 8 + 8x = 4x^2 + 8x
Cancelling the 8x terms, we have:
12x = 4x^2, or 3x = x^2, or x^2 - 3x = 0.
Factoring, we get x(x - 3) = 0, which results in x = 0 and x = 3.
Answer:
58 degrees
Step-by-step explanation:
If angle 1 + angle 2 = 90 degrees, then:
(3x - 4) + (4x+10) = 90
Combine like terms:
(3x+4x) + (10-4) = 90
7x + 6 = 90
Subtract 6 from both sides:
7x = 84
Divide both sides by 7:
x = 12
**Plug x back into angle 2 (This step is easy to forget!):
angle 2 = 4(12) + 10
angle 2 = 48 + 10
angle 2 = 58 degrees