Find an equation for the tangent line to the specified graph at the point given. the graph of y=x^2 at (4, 16). I need detailed explaination because I am just not following. Thanks
your graph is a parabola that runs through the origin, at the point (4,16) we want to find the equation of the tangent line y=mx+b
because the line is tangent to our graph the slope of the tangent line and the slope at the point on our graph are equal
take the derivative of the graph and plug in the value of x to find the slope at that point
y'=2x evaluated at 4 = 8
\[m=\frac{y1-y}{x1-x}=\frac{16-y}{4-x}\]
\[\frac{16-y}{4-x}=8\]
16-y=8(4-x)
how is that 8?
16-32+8x=y and your equation is y=8x-16
m is equal to slope and we no slope is y'=2(4)=8 so we can set them equal to each other
i dont under stand the inverse. it goes from y = x^2 to just 2x?
thats the derivative of the function power rule
d/dx x^n = nx^n-1
oh yeah you bring it out front. ok sorry.
its all good its a tricky question and tough to learn from a message board
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