4. Simplify [tex]\left(16 a^3 b^2 c\right) \times\left(\frac{1}{8} a b\right) \times\left(\frac{1}{4} a^2 b c\right)[/tex] and then evaluate it for [tex]a=-1, b=1, c=-2[/tex].



Answer :

Sure! Let's go through the steps to simplify and evaluate the given expression:

### Step 1: Simplifying the expression

We start with the expression:

[tex]\[ (16 a^3 b^2 c) \times \left(\frac{1}{8} a b\right) \times \left(\frac{1}{4} a^2 b c\right) \][/tex]

First, we will combine the constants and the variables separately.

#### Combining Constants:

[tex]\[ 16 \times \frac{1}{8} \times \frac{1}{4} = 16 \times \frac{1}{32} = \frac{16}{32} = \frac{1}{2} \][/tex]

#### Combining Variables:

Next, we combine the variable parts.

[tex]\[ a^3 \times a \times a^2 = a^{3+1+2} = a^6 \][/tex]

[tex]\[ b^2 \times b \times b = b^{2+1+1} = b^4 \][/tex]

[tex]\[ c \times c = c^2 \][/tex]

Now, we can put everything together:

[tex]\[ \left(16 a^3 b^2 c\right) \times \left(\frac{1}{8} a b\right) \times \left(\frac{1}{4} a^2 b c\right) = \frac{1}{2} \times a^6 \times b^4 \times c^2 \][/tex]

So the simplified expression is:

[tex]\[ \frac{1}{2} a^6 b^4 c^2 \][/tex]

### Step 2: Evaluating the simplified expression

Now we need to evaluate [tex]\(\frac{1}{2} a^6 b^4 c^2\)[/tex] for [tex]\(a = -1\)[/tex], [tex]\(b = 1\)[/tex], and [tex]\(c = -2\)[/tex].

Substitute these values into the simplified expression:

[tex]\[ \frac{1}{2} (-1)^6 (1)^4 (-2)^2 \][/tex]

Calculate the exponents:

[tex]\[ (-1)^6 = 1 \quad (\text{since } (-1) \text{ raised to an even power is 1}) \][/tex]

[tex]\[ (1)^4 = 1 \][/tex]

[tex]\[ (-2)^2 = 4 \][/tex]

Now, substitute these results back into the expression:

[tex]\[ \frac{1}{2} \times 1 \times 1 \times 4 = \frac{1}{2} \times 4 = \frac{4}{2} = 2 \][/tex]

Therefore, the value of the expression when [tex]\(a = -1\)[/tex], [tex]\(b = 1\)[/tex], and [tex]\(c = -2\)[/tex] is:

[tex]\[ 2 \][/tex]

### Final Result

The simplified expression is:

[tex]\[ \frac{1}{2} a^6 b^4 c^2 \][/tex]

And its value for [tex]\(a = -1\)[/tex], [tex]\(b = 1\)[/tex], and [tex]\(c = -2\)[/tex] is:

[tex]\[ 2 \][/tex]