Q. Write an integral expression that will give the length of the path given by f(x)=10x4−1 from x=7 to x=8.
Find Derivative of f(x): To find the length of the path of a function f(x) from x=a to x=b, we use the arc length formula, which is given by the integral:L=∫ab1+[f′(x)]2dxFirst, we need to find the derivative of f(x)=10x4−1.
Substitute into Arc Length Formula: The derivative of f(x)=10x4−1 with respect to x is f′(x)=dxd(10x4−1)=40x3.
Simplify Integral Expression: Now we substitute f′(x) into the arc length formula and simplify: L=∫781+(40x3)2dx
Simplify Integral Expression: Now we substitute f′(x) into the arc length formula and simplify:L=∫781+(40x3)2dx Simplify the expression inside the square root:L=∫781+1600x6dxThis is the integral expression that will give the length of the path of f(x) from x=7 to x=8.
More problems from Evaluate definite integrals using the chain rule