May someone help me find the area along with the upper and lower limit?

Question

anonymous · Answer

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anonymous · Answer

Also a different question. What trig identity would i use for 5cos(2x)

myininaya · Answer

y=e^x
y=e^(-4x)
x=ln(4)

Trying to figure out upper and lower limit.
I have to draw the graph here first. 

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You actually pick the graph that has area bounded by these curves 

Can I ask you what interval of x we are looking at? Like just what you think. I know you are asking. I just want to know what you are thinking.

If you are able to draw the graph, you should see that graph's intersection and know you need to find when e^x is the same as e^(-4x)
or I mean it is actually pretty easy to tell by looking at the graph.