SOLUTION: Find the acute angle that the curve y=1-3x^3 cut the x-axis.

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Question 1161789: Find the acute angle that the curve y=1-3x^3 cut the x-axis.
Found 2 solutions by Alan3354, solver91311:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the acute angle that the curve y=1-3x^3 cut the x-axis.
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Find the x-intercept
3x^3 = 1
x+=+root%283%2C1%2F3%29
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Find the slope at x+=+root%283%2C1%2F3%29
y' = -9x^2
y' = -9%2Aroot%283%2C1%2F9%29
y' =~ -4.3267 at y = 0 = tangent of the angle
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Angle =~ 76.986 degs

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Take the first derivative of the function. Evaluate the function at the zero of the function giving the slope of the tangent line at the x-intercept. The acute angle formed by the tangent line at the intercept is the acute angle formed by the curve at that point. The measure of the angle is the inverse tangent of the slope of the tangent line.


John

My calculator said it, I believe it, that settles it