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Tangent to curve question (1 Viewer)

Trebla

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for what values of b is the line y=3x+b, a tangent to y=x^3
y = x3
dy/dx = 3x2
For the line y = mx + b to be a tangent we require
3x2 = 3
x = -1, 1
Sub this into the curve y = x3 then we get (-1, -1) and (1, 1) as the points of contact.
Since y = 3x + b is a tangent then substituting each of those points allows you to solve for multiple values of b.
 

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