- (
*a*+*b*)(*a*–*b*) = (*a*^{2}–*b*^{2}) - (
*a*+*b*)^{2}= (*a*^{2}+ b^{2}+ 2*ab*) - (
*a*–*b*)^{2}= (*a*^{2}+ b^{2}– 2*ab*) - (
*a*+*b*+*c*)^{2}=*a*^{2}+ b^{2}+*c*^{2}+ 2(*ab*+*bc*+*ca*) - (
*a*^{3}+*b*^{3}) = (*a*+*b*)(*a*^{2}–*ab*+*b*^{2}) - (
*a*^{3}–*b*^{3}) = (*a*–*b*)(*a*^{2}+*ab*+*b*^{2}) - (
*a*^{3}+*b*^{3}+*c*^{3}– 3*abc*) = (*a*+*b*+*c*)(*a*^{2}+*b*^{2}+*c*^{2}–*ab*–*bc*–*ac*) - When
*a*+*b*+*c*= 0, then*a*^{3}+*b*^{3}+*c*^{3}= 3*abc*

Which one of the following is not a prime number? A. 31 B. 61 C. 71 D. 91 Answer: Option D

Explanation:

91 is divisible by 7. So, it is not a prime number.2

(112 x 5 ^{4}) = ?A. 67000 B. 70000 C. 76500 D. 77200 Answer: Option B

Explanation:

(112 x 5 ^{4}) = 112 x10 4 = 112 x 10 ^{4}= 1120000 = 70000 2 2 ^{4}16 -
#### It is being given that (232 + 1) is completely divisible by a whole number. Which of the following numbers is completely divisible by this number?

Correct! Wrong!#### What least number must be added to 1056, so that the sum is completely divisible by 23 ?

Correct! Wrong!#### 1397 x 1397 = ?

Correct! Wrong!#### How many of the following numbers are divisible by 132 ? 264, 396, 462, 792, 968, 2178, 5184, 6336

Correct! Wrong!#### Which of the following is a prime number ?

Correct! Wrong!QUIZ ON NUMBERSWELL DONE !!!Share your Results: