Porisma

A hint to get started

Use a double-angle identity and an exponential substitution

Find

(i) ∫11+cos⁡2x dx\displaystyle\int\dfrac1{1+\cos2x}\,dx. marks

(ii) ∫e2xex+2 dx\displaystyle\int\dfrac{e^{2x}}{e^x+2}\,dx, using the substitution u=ex+2u=e^x+2. marks

[2013/MI/I/8(i),(iii)]

CJC · Review Problems · Question 2

Use the double-angle identity in (i); replace both exe^x and dxdx consistently in (ii).

Read the worked solution