(log10x)2 = log10x2 হলে x এর মান কত?
সমাধান
সঠিক উত্তর: Option C
(log10x)2 = log10x2
বা, (log10x)2 = 2log10x
বা, (log10x)2 - 2log10x = 0
বা, log10x (log10x - 2) = 0
হয়, log10x = 0
বা, x = 100
∴ x = 1
অথবা,
log10x - 2 = 0
বা, log10x = 2
বা, x = 102
∴ x = 100
∴ x = 1, 100
বা, (log10x)2 = 2log10x
বা, (log10x)2 - 2log10x = 0
বা, log10x (log10x - 2) = 0
হয়, log10x = 0
বা, x = 100
∴ x = 1
অথবা,
log10x - 2 = 0
বা, log10x = 2
বা, x = 102
∴ x = 100
∴ x = 1, 100