silemus.

17Tangent line to y=x3y = x^3

Find the equation of the tangent line to y=x3\displaystyle y = x^3 at x=1\displaystyle x = 1, in the form y=mx+c\displaystyle y = mx + c.

Find the point (1,1) from the curve, then the slope from the derivative 3x², giving m=3 at x=1. Plug into y=mx+c to get c=−2, so the tangent is y=3x−2. Check: 3(1)−2=1, matching the curve.

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