2x + 2/x = 3 হলে, x3 + 1/x3 + 2 -এর মান কত?
সমাধান
সঠিক উত্তর: Option B
2x + 2/x = 3
বা,2(x + 1/x) = 3
বা,(x + 1/x) = 3/2
x3+ 1/x3+2 = (x + 1/x)3 - 3x.1/x(x + 1/x) + 2
= (3/2)3 - 3(3/2) + 2
= (27/8) - (9/2) + 2
= (27 - 36 + 16)/8
= 7/8
বা,2(x + 1/x) = 3
বা,(x + 1/x) = 3/2
x3+ 1/x3+2 = (x + 1/x)3 - 3x.1/x(x + 1/x) + 2
= (3/2)3 - 3(3/2) + 2
= (27/8) - (9/2) + 2
= (27 - 36 + 16)/8
= 7/8
