Eight point six two is the answer
<h2>
Hello!</h2>
The answer is:
The correct option is:
C) 
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Why?</h2>
To solve the problem, we need to remember the product of powers with the same base property, the property is defined by the following relation:

If we are multiplying two or more powers with the same base, we must keep the base and add/subtract the exponents.
So, we are given the expression:

We can see that both powers have the same base (4), so solving we have:

Hence, we have that the correct option is:
C) 
Have a nice day!
(cos(x) + cos(y))^2 + (sin(x) - sin(y))^2 Remove the brackets
cos^2(x) + cos^2(y) + 2cos(x)*cos(y) + sin^2(x) - 2(sin(x)*sin(y) + sin^2(y) Combine these two in bold to make 1 because sin^2(x) + cos^2(x) = 1
1 + cos^2(y) + 2cos(x)*cos(y) - 2*sin(x)*cos(y) + sin^2(y)
These two in bold also make 1
2 + 2cos(x)*cos(y) - 2*sin(X)*sin(y) Bring out a common factor of 2
2 +2(cos(x)*cos(y) - sin(x)*sin(y) )
but cos(x+y ) = cos(x)*cos(y) - sin(x)*sin(y)
2 + 2* cos(x + y) is your final answer.
For number 1 the answer is 112