A prime number is a natural number greater than 1 which has no positive divisors other than 1 or itself.
So from above options 2 is that number
2. 587 * 999 = ?
586411
586413
486411
486413
Answer: Option B
Explanation:
Trick: 587 * (1000 - 1) = 587000 - 587 = 586413
3. All prime numbers are odd numbers
True
False
Answer: Option B
Explanation:
It is false, 2 is an even number
4. Find the unit digit in \begin{aligned}
(544)^{102} + (544)^{103}
\end{aligned}
2
4
0
1
Answer: Option C
Explanation:
Required digit is = \begin{aligned}
(4)^{102} + (4)^{103} \end{aligned}
as \begin{aligned} (4)^2 \end{aligned} gives unit digit 6 so \begin{aligned} (4)^{102} \end{aligned} unit digit is 6 and \begin{aligned} (4)^{103} \end{aligned} unit digit is, unit digit of \begin{aligned} 6 \times 4 \end{aligned}= 4, so answer will be unit digit of 6 + 4 = 0
5. Simplify (212 * 212 + 312 * 312 )
132288
142088
142188
142288
Answer: Option D
Explanation:
Trick: Above equation can be solved by using following formula
\begin{aligned}
(a^2 + b^2) = \frac{1}{2}((a+b)^2 + (a-b)^2)
\end{aligned}
