Apply Sum Rule: To find the derivative of the function (21cos2(x)+ln(x)1) with respect to x, we will use the sum rule of differentiation, which states that the derivative of a sum is the sum of the derivatives. We will also need to use the chain rule and the power rule for differentiation.
Derivative of First Term: First, let's find the derivative of the first term 21cos2(x). We will use the chain rule, where the outer function is u2 with u=cos(x), and the inner function is cos(x). The derivative of u2 with respect to u is 2u, and the derivative of cos(x) with respect to x is −sin(x). Applying the chain rule, we get u20.
Derivative of Second Term: Next, we need to find the derivative of the second term ln(x)1. We can rewrite this term as ln(x)−1 and then apply the power rule and the chain rule. The derivative of u−1 with respect to u is −u−2, and the derivative of ln(x) with respect to x is x1. Therefore, the derivative of ln(x)1 with respect to x is ln(x)−10.
Combine Derivatives: Combining the derivatives of both terms, we get the derivative of the entire function:(21cos2(x)+ln(x)1)′=−cos(x)sin(x)−xln(x)21.