Natural exp question Watch

superkinetic
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#1
Report Thread starter 7 years ago
#1
The question is as follows: Given that the curve y = e^{3x} and y = k \sqrt{x} touch each other, show that k = \sqrt{6e}.

Do I have to use any iterative method to prove this?

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ghostwalker
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#2
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(Original post by superkinetic)

Do I have to use any iterative method to prove this?

Thanks
No.
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superkinetic
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(Original post by ghostwalker)
No.
So how do I solve this? I tried squaring both sides but stuck. Thanks
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ghostwalker
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(Original post by superkinetic)
So how do I solve this? I tried squaring both sides but stuck. Thanks
If two curves touch then you know two things regarding their point of contact.

a) They have the same y value at that point.

b) They have the same gradient at that point.

Can you take it from there?
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superkinetic
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(Original post by ghostwalker)
If two curves touch then you know two things regarding their point of contact.

a) They have the same y value at that point.

b) They have the same gradient at that point.

Can you take it from there?
Same gradient! I never thought of that till you mention it. Thanks!
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