Answer:
I + I = II is the answer.
We have 112.5 = 225/2; cos112.5 < 0 because 90 < 112.5 < 180;
cos 112.5 = cos(225/2);
We use the trigonometric formula: cos(x/2) = -

;
Then, cos(225/2) = -

;
We have the formula: cos(270 - x) = -sinx (because cos(a-b) = cosacosb + sinasinb);
Then, cos225 = cos(270-45) = -sin45 = -

Finally, cos112.5 = -
Answer:
x=0
Step-by-step explanation:
factor out 4 from the expression
x - 4 = 1/4 * 4(2x - 4)
Reduce the numbers with the greatest common factor (4)
x - 4 = 2x - 4
cancel equal terms on both sides of the equation
x=2x
move the variable to the left-hand side and change its sign
x - 2x = 0
collect like terms
-x = 0
change the signs on both sides of the equation
x = 0
Hope this helps!!
I believe the answer is 81x^4-16x^2 difference of squares
Answer:
x=30
Step-by-step explanation:
You have to use intercept theorem, also known as Thales's theorem to slvoe this.