x-1x=5 হলে x3-1x3 কত?
A
85
B
105
C
5
D
8
Correct Answer: 85
দেয়া আছে, x3 - 1x3 = (x - 1x)3 + 3× x×1x(x - 1x) = (√5)3 + 3 × √5 = 5√5 + 3√5 = 8√5