4cosasina+cos^2(a)

To simplify the given expression, 4cos(a) + cos^2(a), we can start by factoring out a common factor, which is cos(a):

cos(a)(4 + cos(a))

Since we cannot simplify the expression further, this is the simplified form of the given expression: cos(a)(4 + cos(a)).

To simplify the expression 4cos(a) + cos^2(a), we can substitute cos^2(a) with its equivalent using the identity cos^2(a) = 1 - sin^2(a):

4cos(a) + cos^2(a) = 4cos(a) + 1 - sin^2(a)

Now, let's focus on the term sin^2(a). To simplify this term, we can use the Pythagorean identity sin^2(a) + cos^2(a) = 1. By rearranging this identity, we can solve for sin^2(a):

sin^2(a) = 1 - cos^2(a)

Substituting this back into the original expression:

4cos(a) + cos^2(a) = 4cos(a) + 1 - (1 - cos^2(a))

Now, we can simplify further:

4cos(a) + cos^2(a) = 4cos(a) + 1 - 1 + cos^2(a)

Combine like terms:

4cos(a) + cos^2(a) = 4cos(a) + cos^2(a)

Therefore, the simplified expression is 4cos(a) + cos^2(a).

cosa (4sina+cosa)