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What is the value of this expression when [tex]a=2[/tex] and [tex]b=-3[/tex]?

[tex]\frac{a^3-b^3}{5}[/tex]

A. [tex]-3 \frac{4}{5}[/tex]
B. [tex]-\frac{3}{5}[/tex]
C. 3
D. 7



Answer :

To determine the value of [tex]\(\frac{a^3 - b^3}{5}\)[/tex] when [tex]\(a = 2\)[/tex] and [tex]\(b = -3\)[/tex], let's walk through the calculation step-by-step.

1. Calculate [tex]\(a^3\)[/tex]:
[tex]\[ a^3 = (2)^3 = 2 \times 2 \times 2 = 8 \][/tex]

2. Calculate [tex]\(b^3\)[/tex]:
[tex]\[ b^3 = (-3)^3 = (-3) \times (-3) \times (-3) = -27 \][/tex]

3. Calculate the numerator [tex]\(a^3 - b^3\)[/tex]:
[tex]\[ a^3 - b^3 = 8 - (-27) = 8 + 27 = 35 \][/tex]

4. Divide the result by 5:
[tex]\[ \frac{a^3 - b^3}{5} = \frac{35}{5} = 7 \][/tex]

Therefore, the value of the expression [tex]\(\frac{a^3 - b^3}{5}\)[/tex] when [tex]\(a = 2\)[/tex] and [tex]\(b = -3\)[/tex] is [tex]\(7\)[/tex].

The correct answer is:
[tex]\[ \boxed{7} \][/tex]