Mathematics 9709 · AS & A Level · Logarithmic and exponential functions

Logarithmic and exponential functions — practice question

(i)[5]

Find the value of $x$ in the equation $2\ln(2x) - \ln(x + 3) = 4\ln 2$.

(ii)[2]

Hence, solve the equation $2\ln(2^{u+1}) - \ln(2^u + 3) = 4\ln 2$, giving $u$ correct to $4$ significant figures.

Worked solution & mark scheme

This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Apply $2\ln(2x)=\ln(4x^2)$” …