1 . a+b=5, ab=3

• A. 65
• B. 70
• C. 75
• D. 80

Answer: Option D

Explanation:

2 . a3+b3=

• A. $a^3+b^3+3a^{2}b+3a{b}^2$
• B. ${\left(a+b\right)}^3-3ab\left(a+b\right)$
• C. ${\left(a+b\right)}^3+3ab\left(a+b\right)$
• D. ${\left(a-b\right)}^3-3ab\left(a-b\right)$

Answer: Option B

Explanation:

3 . a3+b3=16

• A. 1
• B. 2
• C. 3
• D. 4

Answer: Option D

Explanation: