Simple question please help (1 Viewer)

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This is a simple question but i think i am missing something and can not get the answer it is
the line y=mx is a tangent to the curve y=e^3x find m
the answer is 3e
thanks in advance
 
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ahhliss

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Is it possible to find it without being given any values of x or y?
Derivative is 3e^3x so isn't that what m is in terms of x's?
 
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i think i just worked it out, is my reasoning correct
y=mx
y'=3e^3x
m =3e^3x
e^3x=3e^3x
x=1/3
m=3e^3(1/3)
m=3e^1
m=3e

im not sure if that is the right working but it gives the right answer
 

Cob-was-here

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FOB all the way said:
i think i just worked it out, is my reasoning correct
y=mx
y'=3e^3x
m =3e^3x
e^3x=3e^3x
x=1/3
m=3e^3(1/3)
m=3e^1
m=3e

im not sure if that is the right working but it gives the right answer
Its right except for where you missed a spot, but i think it's just a typo:
4th line -> e^3x=3xe^3x

this is because y=mx...u forgot the x part
 

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