Question
Factorize the following expressions:
1 - 27a3
1 - 27a3
✓
Answer
1 - 27a3
= (1)3 - (3a)3
= (1 - 3a)(12 + 1 × 3a + (3a)2)
$\therefore$ [a3 - b3 = (a - b)(a2 + ab + b2)]
= (1 - 3a)(12 + 3a + 9a2)
$\therefore$ 1 - 27a3 = (1 - 3a)(12 + 3a + 9a2)
= (1)3 - (3a)3
= (1 - 3a)(12 + 1 × 3a + (3a)2)
$\therefore$ [a3 - b3 = (a - b)(a2 + ab + b2)]
= (1 - 3a)(12 + 3a + 9a2)
$\therefore$ 1 - 27a3 = (1 - 3a)(12 + 3a + 9a2)
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Prove that:
$\frac{\text{x}^{\text{a}(\text{b}-\text{c})}}{\text{x}^{\text{b}(\text{a}-\text{c})}}\div\Big(\frac{\text{x}^\text{b}}{\text{x}^\text{a}}\Big)^\text{c}=1$
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2. What was the total surface area of the tent?
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