If a and b are two odd positive integers, by which of the following integers is (a4 - b4) always divisible?
3
6
8
12
If a and b are odd numbers, then which of the following is even?
a + b + ab
a + b - 1
a + b + 1
a + b + 2ab
If a1/3 = 11, then the value of a2 - 331 a is
1331331
1331000
1334331
1330030
B.
1331000
a1/3 = 11 ⟹ a = 113 = 1331
a2 - 331a = a(a-331)
= 1331(1331 - 331)
= 1331 x 1000 = 1331000