Chapter 5: Q. 5.70 (page 535)

For function $f (x) = x - 7$ and $g (x) = x^{2} + 8 x + 4$ . Find (a) $(f \cdot g) (x)$ (b) $(f \cdot g) (2)$

Short Answer

Expert verified

(a) $(f \cdot g) (x) = x^{3} + x^{2} - 52 x - 28$

(b) $(f \cdot g) (2) = - 120$

Step by step solution

Step 1. Given Information

Given functions $f (x) = x - 7$ and $g (x) = x^{2} + 8 x + 4$ .

We need to find $(f \cdot g) (x) a n d (f \cdot g) (2)$

Part (a) Step 1. Finding f·gx

$(f \cdot g) (x) = f (x) g (x) = (x - 7) (x^{2} + 8 x + 4) (f \cdot g) (x) = x^{3} + 8 x^{2} + 4 x - 7 x^{2} - 56 x - 28 (f \cdot g) (x) = x^{3} + x^{2} - 52 x - 28$

Part (b) Step 1. Finding f·g2

$(f \cdot g) (x) = x^{3} + x^{2} - 52 x - 28 (f \cdot g) (2) = 2^{3} + 2^{2} - 52 (2) - 28 (f \cdot g) (2) = 8 + 4 - 104 - 28 (f \cdot g) (2) = 12 - 132 = - 120$

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For function $f (x) = x - 7$ and $g (x) = x^{2} + 8 x + 4$ . Find (a) $(f \cdot g) (x)$ (b) $(f \cdot g) (2)$

Short Answer

Step by step solution

Step 1. Given Information

Part (a) Step 1. Finding f·gx

Part (b) Step 1. Finding f·g2

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For function fx=x-7and gx=x2+8x+4. Find (a)f·gx(b)f·g2

Short Answer

Step by step solution

Step 1. Given Information

Part (a) Step 1. Finding f·gx

Part (b) Step 1. Finding f·g2

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Math Textbooks

Calculus

Theoretical and Mathematical Physics

Statistics

Probability and Statistics

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Discrete Mathematics

Study anywhere. Anytime. Across all devices.

For function $f (x) = x - 7$ and $g (x) = x^{2} + 8 x + 4$ . Find (a) $(f \cdot g) (x)$ (b) $(f \cdot g) (2)$