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

Logarithmic and exponential functions — practice question

The variables $x$ and $y$ are linked by the equation $5^{y+1} = 2^{3x}$.

(i)[2]

Use logarithms to show that the graph of $y$ plotted against $x$ is a straight line.

(ii)[2]

Find the exact gradient of this line, and state the coordinates of the point where it meets the $y$-axis.

Worked solution & mark scheme

This 4-mark question has a full step-by-step worked solution and mark scheme. One marking point: “State or imply that $(y+1)\log 5=3x\log 2$” …