Q. Given that v=4y4−5, find dyd(3y3−5sinv) in terms of only y.Answer:
Find Derivative with Chain Rule: First, we need to find the derivative of the function 3y3−5sin(v) with respect to y. To do this, we will use the chain rule, which states that the derivative of a composite function is the derivative of the outer function times the derivative of the inner function. In this case, the outer function is 3y3−5sin(u) (where u is a function of y), and the inner function is v=4y4−5.
Differentiate Outer Function: We start by differentiating the outer function with respect to u, treating u as the variable. The derivative of 3y3 with respect to u is 0, since it does not contain the variable u. The derivative of −5sin(u) with respect to u is −5cos(u). So, the derivative of the outer function with respect to u is −5cos(u).
Differentiate Inner Function: Next, we need to differentiate the inner function v=4y4−5 with respect to y. The derivative of 4y4 with respect to y is 16y3, and the derivative of −5 with respect to y is 0. Therefore, the derivative of v with respect to y is 16y3.
Apply Chain Rule: Now, we apply the chain rule by multiplying the derivative of the outer function with respect to u by the derivative of the inner function with respect to y. This gives us the derivative of 3y3−5sin(v) with respect to y as −5cos(v)⋅16y3.
Express Derivative in Terms of y: Finally, we need to express the derivative in terms of y only. Since v=4y4−5, we substitute v back into our expression for the derivative. This gives us the final derivative as −5cos(4y4−5)×16y3.
More problems from Write a formula for an arithmetic sequence