Westonci.ca connects you with experts who provide insightful answers to your questions. Join us today and start learning! Get quick and reliable solutions to your questions from a community of experienced professionals on our platform. Connect with a community of professionals ready to provide precise solutions to your questions quickly and accurately.

16. Let [tex]$n$[/tex] be a particular integer in [tex]\mathbb{Z}^{+}[/tex]. Describe the elements of the residue class(es) for [tex]$n=1, 2, \ldots, 7$[/tex].

If [tex]$f, g: \mathbb{R} \longrightarrow \mathbb{R}$[/tex] are given by [tex][tex]$f(x) = x^2 + 2x - 3$[/tex][/tex] and [tex]$g(x) = 3x - 4$[/tex], find [tex](f \circ g)(x)[/tex].

Sagot :

Certainly! Let's solve the problem step by step.

Given the functions [tex]\( f \)[/tex] and [tex]\( g \)[/tex]:

[tex]\[ f(x) = x^2 + 2x - 3 \][/tex]
[tex]\[ g(x) = 3x - 4 \][/tex]

We need to find the composition [tex]\( (f \circ g)(x) \)[/tex], which is essentially [tex]\( f(g(x)) \)[/tex]. This means that we will first apply [tex]\( g(x) \)[/tex] and then apply [tex]\( f \)[/tex] to the result of [tex]\( g(x) \)[/tex].

1. Calculate [tex]\( g(x) \)[/tex]:

[tex]\[ g(x) = 3x - 4 \][/tex]

2. Substitute [tex]\( g(x) \)[/tex] into [tex]\( f \)[/tex]:

[tex]\[ f(g(x)) = f(3x - 4) \][/tex]

3. Replace [tex]\( x \)[/tex] in [tex]\( f(x) \)[/tex] with [tex]\( 3x - 4 \)[/tex]:

[tex]\[ f(3x - 4) = (3x - 4)^2 + 2(3x - 4) - 3 \][/tex]

4. Expand [tex]\( (3x - 4)^2 \)[/tex]:

[tex]\[ (3x - 4)^2 = 9x^2 - 24x + 16 \][/tex]

5. Calculate [tex]\( 2(3x - 4) \)[/tex]:

[tex]\[ 2(3x - 4) = 6x - 8 \][/tex]

6. Combine all the terms:

[tex]\[ f(3x - 4) = 9x^2 - 24x + 16 + 6x - 8 - 3 \][/tex]

7. Simplify the expression:

[tex]\[ f(3x - 4) = 9x^2 - 18x + 5 \][/tex]

Thus, the composite function [tex]\( (f \circ g)(x) \)[/tex] is:

[tex]\[ (f \circ g)(x) = 9x^2 - 18x + 5 \][/tex]

To verify, let's evaluate [tex]\( (f \circ g)(x) \)[/tex] for a range of integer values of [tex]\( x \)[/tex] from [tex]\(-10\)[/tex] to [tex]\(10\)[/tex]:

[tex]\[ \begin{align*} (f \circ g)(-10) & = 9(-10)^2 - 18(-10) + 5 = 900 + 180 + 5 = 1085, \\ (f \circ g)(-9) & = 9(-9)^2 - 18(-9) + 5 = 729 + 162 + 5 = 896, \\ (f \circ g)(-8) & = 9(-8)^2 - 18(-8) + 5 = 576 + 144 + 5 = 725, \\ (f \circ g)(-7) & = 9(-7)^2 - 18(-7) + 5 = 441 + 126 + 5 = 572, \\ (f \circ g)(-6) & = 9(-6)^2 - 18(-6) + 5 = 324 + 108 + 5 = 437, \\ (f \circ g)(-5) & = 9(-5)^2 - 18(-5) + 5 = 225 + 90 + 5 = 320, \\ (f \circ g)(-4) & = 9(-4)^2 - 18(-4) + 5 = 144 + 72 + 5 = 221, \\ (f \circ g)(-3) & = 9(-3)^2 - 18(-3) + 5 = 81 + 54 + 5 = 140, \\ (f \circ g)(-2) & = 9(-2)^2 - 18(-2) + 5 = 36 + 36 + 5 = 77, \\ (f \circ g)(-1) & = 9(-1)^2 - 18(-1) + 5 = 9 + 18 + 5 = 32, \\ (f \circ g)(0) & = 9(0)^2 - 18(0) + 5 = 0 + 0 + 5 = 5, \\ (f \circ g)(1) & = 9(1)^2 - 18(1) + 5 = 9 - 18 + 5 = -4, \\ (f \circ g)(2) & = 9(2)^2 - 18(2) + 5 = 36 - 36 + 5 = 5, \\ (f \circ g)(3) & = 9(3)^2 - 18(3) + 5 = 81 - 54 + 5 = 32, \\ (f \circ g)(4) & = 9(4)^2 - 18(4) + 5 = 144 - 72 + 5 = 77, \\ (f \circ g)(5) & = 9(5)^2 - 18(5) + 5 = 225 - 90 + 5 = 140, \\ (f \circ g)(6) & = 9(6)^2 - 18(6) + 5 = 324 - 108 + 5 = 221, \\ (f \circ g)(7) & = 9(7)^2 - 18(7) + 5 = 441 - 126 + 5 = 320, \\ (f \circ g)(8) & = 9(8)^2 - 18(8) + 5 = 576 - 144 + 5 = 437, \\ (f \circ g)(9) & = 9(9)^2 - 18(9) + 5 = 729 - 162 + 5 = 572, \\ (f \circ g)(10) & = 9(10)^2 - 18(10) + 5 = 900 - 180 + 5 = 725. \end{align*} \][/tex]

Therefore, the values of [tex]\((f \circ g)(x)\)[/tex] for [tex]\(x\)[/tex] in the range [tex]\([-10, 10]\)[/tex] are:

[tex]\[ [1085, 896, 725, 572, 437, 320, 221, 140, 77, 32, 5, -4, 5, 32, 77, 140, 221, 320, 437, 572, 725] \][/tex]
We appreciate your time. Please come back anytime for the latest information and answers to your questions. We hope this was helpful. Please come back whenever you need more information or answers to your queries. Westonci.ca is committed to providing accurate answers. Come back soon for more trustworthy information.