Theory question 102
Indices and LogarithmsSolve 2(2y+1) − 5(2y) + 2 = 0
Show the model answer
Model answer
Let p = 2ʸ: 2p² − 5p + 2 = 0, (2p − 1)(p − 2) = 0.
p = ½: 2ʸ = 2⁻¹, y = −1. p = 2: y = 1.
y = −1 or y = 1.
Explanation
2^(2y + 1) = 2 × (2ʸ)².