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How do I solve this problem?

How do I solve this problem?-example-1
User Delvin
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1 Answer

9 votes
9 votes

Answer:

y = 16(x +2)

Explanation:

The equation of the tangent to a curve at a point can be written using the point-slope form of the equation for a line. The point is (x, f(x)), and the slope is the derivative, f'(x).

Point and slope

The point where you want the tangent line has y-value ...

y = 2(-2)³ -8(-2) = 2(-8)+2(8) = 0 . . . . . point (x, y) = (-2, 0)

The slope at the point where you want the tangent is ...

y' = 2·3x² -8 = 6(-2)² -8 = 24 -8 = 16 . . . . . slope m = 16

Equation of the tangent line

The point-slope equation of a line is ...

y -k = m(x -h) . . . . . line with slope m through point (h, k)

y -0 = 16(x -(-2)) . . . . . line with slope 16 through (-2, 0)

y = 16(x +2) . . . . . simplified

An equation of the tangent line is ...

y = 16(x +2)

How do I solve this problem?-example-1
User Strangfeld
by
2.9k points