examday

Official papers

Official 2020 Paper 1 · Q15

Paper 1Powers & logarithms

Find the positive difference between the two real values of xx for which

(log⁡2x)4+12(log⁡2(1x))2−26=0(\log_2 x)^4+12\left(\log_2\left(\frac1x\right)\right)^2-2^6=0
A44
B1616
C154\frac{15}4
D174\frac{17}4
E25516\frac{255}{16}
F25716\frac{257}{16}

Read the questions freely. Sign in to check your answer, see the worked solution and save your progress.

Sign in to check your answerPractise the whole paper →