(main)[4]
With $u = e^x$ as the substitution, solve the equation $4e^{-x} = 3e^x + 4$. State your answer correct to 3 significant figures.
Mathematics 9709 · AS & A Level · Logarithmic and exponential functions
Logarithmic and exponential functions — practice question
Worked solution & mark scheme
This 4-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Put it into the form $3u^2+4u-4=0$, or $3e^{2x}+4e^x-4=0$, or an equivalent form” …
- Full mark scheme, point by point
- Step-by-step worked solution
- Write your answer & get it marked instantly by AI