How do you graph #y=-2^x#?

1 Answer
May 14, 2018

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Create a data table to graph the exponential function : #color(red)(y=-2^x#

Explanation:

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#color(green)("Step 1 :"#

Create a data table:

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Closely examine the values for #x# and #y#

No value of #x# makes #y# zero.

So, the graph gets closer and closer to the x-axis but never touches the x-axis.

Hence, #color(brown)(y=0# is the horizontal asymptote.

#color(green)("Step 2 :"#

Using the data table, graph the function #y =f(x)=-2^x#

For easy comprehension, graph the exponential function #y=f(x)=2^x#, it's parent function.

Compare both the graphs to understand the behavior of the given exponential function #y=f(x)=-2^x#

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The graph of #y =f(x)=-2^x# is reflected about the x-axis when the sign of #f(x)# is negative.