Question

The variables X, Y, and Z represent polynomials where X = a, Y = 3a – 5, and Z = a^2 + 2. What is X^2Y – Z in simplest form?

a. 2a^2 – 5a – 2
b. 3a^3 – 6a^2 – 2
c. –3a^3 – 2
d. –3a^2 – 2

Answer 1

`X=a \\ Y=3a-5 \\ Z=a^2+2 \\ \\ X^2Y-Z=a^2(3a-5)-(a^2+2)=3a^3-5a^2-a^2-2=3a^3-6a^2-2`

The answer is b.

Answer 2

Answer: Option 'b' is correct.

Explanation:

Since we have given that

`X=a\\\\Y=3a-5\\\\Z=a^2+2`

We need to calculate :

`X^2Y-Z`

So, we put the values of X, Y, and Z in the expression, then it becomes,

`X^2Y-Z=a^2(3a-5)-(a^2+2)\\\\X^2Y-Z=3a^3-5a^2-a^2-2\\\\X^2Y-Z=3a^3-6a^2-2`

Hence, Option 'b' is correct.