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This question assumes you understand the definition and the laws of logarithms.

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a) To find the $x$-intercept, substitute $y=0$ into the equation: $0=\\log_{\\var{b}}(x)$ which is equivalent to $\\var{b}^0=x$, i.e. $x=1$. Therefore, the $x$-intercept is the point $(1,0)$.

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b) Substitute $y=1$ into the equation: $1=\\log_{\\var{b}}(x)$ which is equivalent to $\\var{b}^1=x$, i.e. $x=\\var{b}$. Therefore, another easily found point is $(\\var{b},1)$.

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c) Let's investigate what happens to the value of $y$ when the value of $x$ is increased by a factor of $\\var{b}$:

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\\[\\log_{\\var{b}}(\\var{b}x)=\\log_{\\var{b}}(\\var{b})+\\log_{\\var{b}}(x)=1+\\log_{\\var{b}}(x)\\]

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This is the old $y$ value plus 1, so we can say that $y$ is increased by 1.

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d) As $x$ gets larger and larger, $y$ gets larger and larger. Even though the rate of increase slows, $y$ continues to grow without bound.

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e) An asymptote is a line or curve that approaches a given curve arbitrarily closely. For the curve $y=\\log_{\\var{b}}(x)$ the closer $x$ gets to zero (approaching from the right), the smaller $y$ gets (without bound). In other words, as $x$ approaches $0$ from the right, $y$ approaches negative infinity. This means that the asymptote for $y=\\log_{\\var{b}}(x)$ is the line $x=0$ (the $y$-axis).

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f) Given all the information above, it should be clear that the graph should look like 

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{graph1(1)}

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The easiest type of exponential to graph where the base is greater than 1 and no transformations take place.

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The $x$-intercept of $y=\\log_{\\var{b}}(x)$ is the point $\\large($[[0]], [[1]]$\\large)$.

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Another easily found point on the curve is $\\large($[[0]], $\\large1 )$.

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increases by 1.

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decreases by 1.

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increases by {b-1}.

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decreases by {b-1}.

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increases by a factor of {b}.

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decreases by a factor of {b}.

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Given $y=\\log_{\\var{b}}(x)$, everytime $x$ increases by a factor of $\\var{b}$, $y$  [[0]].

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$y$ approaches $0$.

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$y$ decreases without bound.

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$y$ increases without bound.

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$y$ approaches $\\var{b}$.

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As $x$ increases without bound, [[0]]

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The vertical asymptote of $y=\\log_{\\var{b}}(x)$ is $x=$ [[0]].

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{graph1(1)}

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{graph1(2)}

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{graph1(3)}

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{graph1(4)}

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Which graph best represents $y=\\log_{\\var{b}}(x)$?

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The following questions will gauge your understanding of logarithms and how to graph them. 

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The logarithm you will be working with for this question is \\[y=\\log_{\\var{b}}(x).\\]

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