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A hint to get started

Repeat a logarithmic segment with the correct jump values

Let f(x)=ln⁡xf(x)=\ln x for 1≤x≤e1\le x\le e, and f(x)=0f(x)=0 for e<x≤3e<x\le3, with f(x+2)=f(x)f(x+2)=f(x) for all real xx.

(a) Rotate the region bounded by y=f(x)y=f(x), the x-axis and x=ex=e through 2π2\pi about the x-axis. Find the exact volume.

(b) Sketch y=f(x)y=f(x) for −3≤x≤4-3\le x\le4. Hence find ∫−34f(x)dx\int_{-3}^4f(x)dx.

[2014/ACJC/I/10(ii)]

CJC · Review problems · Question 14

Translate the argument inside the logarithm and preserve the jump endpoint values.

Read the worked solution