ab = ba, a = 2b, a ≠ 0 হলে, (a, b) = ?
সমাধান
সঠিক উত্তর: Option B
ab = ba
or, Inab = In ba [In নিয়ে]
or, bIna = aInb
or, Ina = (a/b)Inb
or, Ina = Inb(a/b)
or, a = b(a/b)
or, a = b(2b/b)
or, a = b2
or, b2 = 2b [a=2b]
or, b(b - 2) = 0
or, b = 2
∴ a = 2b
= 2 x 2
= 4
∴ (a,b)=(4,2)
or, Inab = In ba [In নিয়ে]
or, bIna = aInb
or, Ina = (a/b)Inb
or, Ina = Inb(a/b)
or, a = b(a/b)
or, a = b(2b/b)
or, a = b2
or, b2 = 2b [a=2b]
or, b(b - 2) = 0
or, b = 2
∴ a = 2b
= 2 x 2
= 4
∴ (a,b)=(4,2)
