Simplify the expression:

[tex]\[ \left[a^2 b^3 - 6y^2 + \frac{3}{5} a^2 b^3 - 18xy^2 - 30\right] \times \left[\frac{6}{3} a^2 b^3 + \frac{21}{3} a^2 b^3\right] \][/tex]



Answer :

Sure, let's solve this step-by-step.

### Step 1: Simplify Each Polynomial Inside the Brackets

#### Left Bracket: [tex]\([a^2 b^3 - 6 y^2 + \frac{3}{5} a^2 b^3 - 18 x y^2 - 30]\)[/tex]

1. Combine like terms:
- [tex]\(a^2 b^3\)[/tex] and [tex]\(\frac{3}{5} a^2 b^3\)[/tex]
[tex]\[ a^2 b^3 + \frac{3}{5} a^2 b^3 = \left(1 + \frac{3}{5}\right) a^2 b^3 = \frac{5}{5} a^2 b^3 + \frac{3}{5} a^2 b^3 = \frac{8}{5} a^2 b^3 \][/tex]

2. Bring all terms together:
[tex]\[ \frac{8}{5} a^2 b^3 - 6 y^2 - 18 x y^2 - 30 \][/tex]

So, the left bracket simplifies to:
[tex]\[ \left[\frac{8}{5} a^2 b^3 - 6 y^2 - 18 x y^2 - 30\right] \][/tex]

#### Right Bracket: [tex]\[\left[\frac{6}{3} a^2 b^3 + \frac{21}{3} a^2 b^3\right]\][/tex]

Here, each term is already simplified:
1. [tex]\(\frac{6}{3} a^2 b^3\)[/tex] simplifies to [tex]\(2 a^2 b^3\)[/tex].
2. [tex]\(\frac{21}{3} a^2 b^3\)[/tex] simplifies to [tex]\(7 a^2 b^3\)[/tex].

Combine the terms:
[tex]\[ 2 a^2 b^3 + 7 a^2 b^3 = 9 a^2 b^3 \][/tex]

So, the right bracket simplifies to:
[tex]\[ \left[9 a^2 b^3\right] \][/tex]

### Step 2: Multiply the Simplified Expressions

Now we need to multiply the expressions from the left bracket and the right bracket:
[tex]\[ \left[\frac{8}{5} a^2 b^3 - 6 y^2 - 18 x y^2 - 30\right] \times \left[9 a^2 b^3\right] \][/tex]

Distribute [tex]\(9 a^2 b^3\)[/tex] to each term in the left bracket:

1. [tex]\[ \left(\frac{8}{5} a^2 b^3\right) \times \left(9 a^2 b^3\right) \][/tex]
[tex]\[ = \frac{8}{5} \times 9 \times a^2 b^3 \times a^2 b^3 \][/tex]
[tex]\[ = \frac{72}{5} a^4 b^6 \][/tex]

2. [tex]\[ -6 y^2 \times 9 a^2 b^3 \][/tex]
[tex]\[ = -54 a^2 b^3 y^2 \][/tex]

3. [tex]\[ -18 x y^2 \times 9 a^2 b^3 \][/tex]
[tex]\[ = -162 x a^2 b^3 y^2 \][/tex]

4. [tex]\[ -30 \times 9 a^2 b^3 \][/tex]
[tex]\[ = -270 a^2 b^3 \][/tex]

### Step 3: Combine All Results
Thus, multiplying the initial polynomials together, we get:
[tex]\[ = \frac{72}{5} a^4 b^6 - 54 a^2 b^3 y^2 - 162 x a^2 b^3 y^2 - 270 a^2 b^3 \][/tex]

This is the simplified result from multiplying the two given polynomials.

So, your final answer is:
[tex]\[ \boxed{\frac{72}{5} a^4 b^6 - 54 a^2 b^3 y^2 - 162 x a^2 b^3 y^2 - 270 a^2 b^3} \][/tex]