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What polynomial identity should be used to prove that 35 = 8 + 27

2 Answers

1 vote

Answer:

Sum of cubes

Explanation:

I just did the assignment

User Norayr Ghukasyan
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6 votes

Answer:

Sum of cubes identity should be used to prove 35 =3+27

Explanation:

Prove that : 35 = 8 +27

Polynomial identities are just equations that are true, but identities are particularly useful for showing the relationship between two apparently unrelated expressions.

Sum of the cubes identity:


a^3+b^3=(a+b)(a^2-ab+b^2)

Take RHS

8+ 27

We can write 8 as
2 * 2 * 2 = 2^3 and 27 as
3 * 3 * 3 = 3^3.

then;

8+27 =
2^3+3^3

Now, use the sum of cubes identity;

here a =2 and b = 3


2^3+3^3 = (2+3)(2^2-2\cdot 3+3^2)

or


2^3+3^3 = (5)(4-6+9)
= 5 \cdot 7 = 35 = LHS proved!

therefore, the Sum of cubes polynomial identity should be used to prove that 35 = 8 +27

User Pan Ziyue
by
7.7k points