Cos(2x) = cos^2(x) - sin^2(x) - cos(x)
but sin^2(x) = 1 - cos^2(x)
cos(2x) - cos(x) = cos^2(x) - (1 - cos^2(x) ) - cos(x)
cos(2x) - cos(x) = cos^2(x) - 1 + cos^2(x) - cos(x)
cos(2x) - cos(x) = 2cos^2(x) - 1 - cos(x)
cos(2x) - cos(x) = (2cos(x) + 1)(cos(x) - 1)
I think this is what you have asked for.
Answer:
x= -19
Step-by-step explanation:
-3 + x = -22
Add 3 to each side
-3+3 +x = -22 +3
x = -19
This can be solve by establishing equations.
let x be the miles mrs. storey drove
y be the miles mr storey drovee
the first equation is
y = 3x
second equation
x + y = 3200
then substitute equation 1
x + 3x = 3200
4x = 3200
x = 800 miles mrs storey drove
y = 3x = 2400 miles mr storey drove
Answer:
.163
Step-by-step explanation:
not sure what so ever that is a hard question