Estimate Smallest Distance Between (0,0) and y=e^x

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"Using IVT and RT work out an estimate for the smallest distance between the point (0,0) and the curve
y = e^x "
Can anyone help me with this question? Thanks.


Note: IVT is "Intermediate Value Theorem" and RT is "Rolle's Theorem"
 
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What is the function for distance between the points (0,0) and (x,e^x)?
 
d2=x2+e2x

RT says there is a point where the tangent (to d2) is horizontal, since the function ->+∞ for both x and -x ->∞. This would be the minimum.

Use IVT on the derivative of x2 let's you find the minimum (0 derivative), since the derivative goes to +∞ as x goes to +∞, while it goes to -∞ as x goes to -∞.
 
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