(i)[3]
If $5^{2x} + 5^x = 12$, determine the value of $5^x$.
(ii)[2]
Therefore, use logarithms to solve $5^{2x} + 5^x = 12$, and give the value of $x$ 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 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Write, or indicate, the equation in the form $(5^{x})^2 + 5^x - 12 = 0$” …
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