Since we know a = 3, substitute this into the expression:
2a² = 2 x 3²
3² = 9
So 2a² = 2 x 9
2a² = 18
We know b = 2 and c = 1, so substitute these values into the expression:
3b² - c³ = 3 x 2² - 1³
2² = 4
1³ = 1
So:
3 x 4 - 1
Using the order of operations we multiply first:
3 x 4 = 12
Take off the 1:
Final answer:
3b² - c³ = 11
