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CAIE pure math P2&3 Logarithmic and Exponential Functions question

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Hey guys, can you tell me how to calculate the C and a?
 

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y=C(ax)\rightarrow y = C(a^x)
ln(y)=ln(c)+xln(a)\rightarrow ln(y) = ln(c) + xln(a)
ln(y)=ln(a)x+ln(c)\rightarrow ln(y) = ln(a)x + ln(c)

    gradient=ln(a)\implies gradient = ln(a)
    yintercept=ln(c)\implies y-intercept = ln(c)

\rarr You can now sketch the graph and find what's the gradient and y-intercept.
rarrrarr Then use the above two equations for gradient and y-intercept to find the values of a and c respectively.
 
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31
Reaction score
4
Points
8
y=C(ax)\rightarrow y = C(a^x)
ln(y)=ln(c)+xln(a)\rightarrow ln(y) = ln(c) + xln(a)
ln(y)=ln(a)x+ln(c)\rightarrow ln(y) = ln(a)x + ln(c)

    gradient=ln(a)\implies gradient = ln(a)
    yintercept=ln(c)\implies y-intercept = ln(c)

\rarr You can now sketch the graph and find what's the gradient and y-intercept.
rarrrarr Then use the above two equations for gradient and y-intercept to find the values of a and c respectively.
I have used your idea to done. But I calculate the gradient is 0.39? Is right?
 
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