MCQ
The product $(x^2 - 1)(x^4 + x^2 + 1)$ is equal to:
- A$x^8 - 1$
- B$x^8 + 1$
- ✓$x^6 - 1$
- D$x^6+ 1$
✓
Answer
Correct option: C.
$x^6 - 1$
Given expression is $\left(x^2-1\right)\left(x^4+x^2+1\right)$
Let ${x}^2={A}$ and $1=\mathrm{B}$
Then, we have
$(A-B)\left(A^2+A B+B^2\right)$
$= A^3-B^3$
$= (X^2)^3-(1)^3$
$= X^6-1$
Hence, correct option is $(c).$
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