Question

if a=2 and b=-3 what is the value of 3a^2 + 5^ab

Answer 1

The expression "3a^2 + 5^ab" is ambiguous: it could mean 3a^2 + (5^a)·b or 3a^2 + 5^{ab}. I’ll evaluate both for a = 2, b = −3.

1) If it means 3a^2 + (5^a)·b:
- 3a^2 = 3·2^2 = 3·4 = 12
- 5^a·b = 5^2·(−3) = 25·(−3) = −75
- Total = 12 − 75 = −63

2) If it means 3a^2 + 5^{ab}:
- 3a^2 = 12 (as above)
- 5^{ab} = 5^{2·(−3)} = 5^{−6} = 1/5^6 = 1/15625
- Total = 12 + 1/15625 = 187501/15625 ≈ 12.000064

Tell me which interpretation you intended and I’ll confirm.