13.3: Exercises
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Graph the following functions with the calculator.
- y=5x
- y=1.01x
- y=(13)x
- y=0.97x
- y=3−x
- y=(13)−x
- y=ex2
- y=0.01x
- y=1x
- y=ex+1
- y=ex−e−x2
- y=ex−e−xex+e−x
The last two functions are known as the hyperbolic sine, sinh(x)=ex−e−x2, and the hyperbolic tangent, tanh(x)=ex−e−xex+e−x. Recall that the hyperbolic cosine cosh(x)=ex+e−x2 was already graphed in example hyperbolic-cosine.
- Answer
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- same as c) since y=(13)x=3−x
Graph the given function. Describe how the graph is obtained by a transformation from the graph of an exponential function y=bx (for appropriate base b).
- y=0.1⋅4x
- y=3⋅2x
- y=(−1)⋅2x
- y=0.006⋅2x
- y=e−x
- y=e−x+1
- y=(12)x+3
- y=2x−4
- y=2x+1−6
- Answer
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- y=4x is compressed towards the x-axis by the factor 0.1
- y=2x stretched away from x-axis
- y=2x reflected about the x-axis
- y=2x compressed towards the x-axis
- y=ex reflected about the y-axis
- y=ex reflected about the y-axis and shifted up by 1
- y=(12)x shifted up by 3
- y=2x shifted to the right by 4
- y=2x shifted to the left by 1 and down by 6
- y=4x is compressed towards the x-axis by the factor 0.1
Use the definition of the logarithm to write the given equation as an equivalent logarithmic equation.
- 42=16
- 28=256
- ex=7
- 10−1=0.1
- 3x=12
- 57⋅x=12
- 32a+1=44
- (12)xh=30
- Answer
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- log4(16)=2
- log2(256)=8
- ln(7)=x
- log(0.1)=−1
- log3(12)=x
- log5(12)=7x
- log3(44)=2a+1
- log12(30)=xh
Evaluate the following expressions without using a calculator.
- log7(49)
- log3(81)
- log2(64)
- log50(2,500)
- log2(0.25)
- log(1,000)
- ln(e4)
- log13(13)
- log(0.1)
- log6(136)
- ln(1)
- log12(8)
- Answer
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- 2
- 4
- 6
- 2
- −2
- 3
- 4
- 1
- −1
- −2
- 0
- −3
Using a calculator, approximate the following expressions to the nearest thousandth.
- log3(50)
- log3(12)
- log17(0.44)
- log0.34(200)
- Answer
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- 3.561
- 2.262
- −0.290
- −4.911
State the domain of the function f and sketch its graph.
- f(x)=log(x)
- f(x)=log(x+7)
- f(x)=ln(x+5)−1
- f(x)=ln(3x−6)
- f(x)=2⋅log(x+4)
- f(x)=−4⋅log(x+2)
- f(x)=log3(x−5)
- f(x)=−ln(x−1)+3
- f(x)=log0.4(x)
- f(x)=log3(−5x)−2
- f(x)=log|x|
- f(x)=log|x+2|
- Answer
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