Chapter 5: Q. 92 (page 285)

Suppose that $f (x) = 3^{x}$ .
(a) What is $f (4)$ ? What point is on the graph of f?
(b) If $f (x) = \frac{1}{9}$ , what is x? What point is on the graph of f?

Short Answer

Expert verified

Part (a) $f (4) = 81$ and the point on graph is $(4, 81)$ .

Part (b) $x = - 2$ and the point on the graph is $(- 2, \frac{1}{9})$ .

Step by step solution

Part (a) Step 1. Substitute x=4 in f(x)=3x.

This gives

$f (4) = 3^{4} f (4) = 81$

The point on the graph of the function f is $(4, 81)$ .

Part (b) Step 1. Finding value of x using f(x)=19.

This gives

$f (x) = \frac{1}{9} 3^{x} = \frac{1}{9} 3^{x} = 9^{- 1} 3^{x} = {(3^{2})}^{- 1} 3^{x} = 3^{- 2}$

On comparing

$x = - 2$

The point on the graph of the function f is $(- 2, \frac{1}{9})$ .

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Suppose that $f (x) = 3^{x}$ .
(a) What is $f (4)$ ? What point is on the graph of f?
(b) If $f (x) = \frac{1}{9}$ , what is x? What point is on the graph of f?

Short Answer

Step by step solution

Part (a) Step 1. Substitute x=4 in f(x)=3x.

Part (b) Step 1. Finding value of x using f(x)=19.

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Suppose that f(x)=3x.(a) What is f(4)? What point is on the graph of f?(b) If f(x)=19, what is x? What point is on the graph of f?

Short Answer

Step by step solution

Part (a) Step 1. Substitute x=4 in f(x)=3x.

Part (b) Step 1. Finding value of x using f(x)=19.

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Math Textbooks

Geometry

Statistics

Logic and Functions

Discrete Mathematics

Mechanics Maths

Theoretical and Mathematical Physics

Study anywhere. Anytime. Across all devices.

Suppose that $f (x) = 3^{x}$ .
(a) What is $f (4)$ ? What point is on the graph of f?
(b) If $f (x) = \frac{1}{9}$ , what is x? What point is on the graph of f?