2.20: Differentiation leading to integration

0606/21/O/N/17 — Question 5 · 6 marks

(i)
Find ddx(53x+2)\dfrac{\mathrm{d}}{\mathrm{d}x}\left(\dfrac{5}{3x + 2}\right).
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(ii)
Use your answer to part (i) to find 30(3x+2)2dx\displaystyle\int \frac{30}{(3x + 2)^{2}}\,\mathrm{d}x.
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(iii)
Hence evaluate 1230(3x+2)2dx\displaystyle\int_{1}^{2} \frac{30}{(3x + 2)^{2}}\,\mathrm{d}x.
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