Question

Find x, if 2 log₂ x = 4

 (A) 4, -4

(B) 4

(C) -4

(D) not defined

Answer 1

(B) 4

2 log₂ x = 4, x > 0

∴ log₂ (x²) = 4

∴ x² = 16

∴ x = ±4

∴ x = 4