Which differential element must be used to express the exact arc length of a…

MATHEMATICS · Single correct · AP · Calculus BC · Applications of Integration · Applications of Integration

Problem

Which differential element must be used to express the exact arc length

L

of a differentiable function

y=f(x)

on the interval

[a,b]

? (a)

\sqrt{1+\left(\dfrac{dy}{dx}\right)^2}\,dx

(b)

\sqrt{\left(\dfrac{dy}{dx}\right)^2}\,dx

(c)

(1+\left(\dfrac{dy}{dx}\right)^2)dx

(d)

\sqrt{1+\left(\dfrac{dx}{dy}\right)^2}\,dx