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:
a=19
Step-by-step explanation:
First we have to distribute the parenthesis; multiply (a+5) by 1/3
8=1/3*a+1/3*5
Now we just solve the equation regularly
8=1/3a+5/3
8-5/3=1/3a
6 1/3=1/3a
a=19
Answer:
The number is 12
Step-by-step explanation:
Let x be the number
160/100 = 1.6
1.6 x = 19.2
x = 19.2 / 1.6
x = 12
Answer:The angles are 63 degrees and 27 degrees
This is true because when you subtract 27 from 63 you get 36. And when you add 27 to 63 you get 90 aka the complimentary angle we’re looking for.
Answer:
The value of rate per annum is R = 12.5 %
Step-by-step explanation:
Principal amount = 576
Interest = 153
Amount after 2 years = 576 + 153 = 729
We know that
![A = P [1 + \frac{R}{100} ] ^{T}](https://tex.z-dn.net/?f=A%20%3D%20P%20%5B1%20%2B%20%5Cfrac%7BR%7D%7B100%7D%20%5D%20%5E%7BT%7D)
Put all the values in above equation
![729 = 576 [1 + \frac{R}{100} ]^{2}](https://tex.z-dn.net/?f=729%20%3D%20576%20%5B1%20%2B%20%5Cfrac%7BR%7D%7B100%7D%20%5D%5E%7B2%7D)
R = 12.5 %
This is the value of rate per annum.
