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The equation of the tangent line to the curve y=x2−2x+5y = x^2 - 2x + 5 which is parallel to the line 4x−y+1=04x - y + 1 = 0 is

Solution

✅ Correct Option: 2

The line 4x−y+1=04x - y + 1 = 0 can be rewritten as:

y=4x+1y = 4x + 1

The slope of this line =4= 4.

Since the tangent line must be parallel, the required tangent also has slope =4= 4.


The curve is:

y=x2−2x+5y = x^2 - 2x + 5

dydx=2x−2\frac{dy}{dx} = 2x - 2

Setting the derivative equal to 44:

2x−2=42x - 2 = 4

2x=62x = 6

x=3x = 3

Substituting x=3x = 3 back into the curve:

y=(3)2−2(3)+5y = (3)^2 - 2(3) + 5

y=9−6+5y = 9 - 6 + 5

y=8y = 8

The point of tangency is (3, 8)(3,\ 8).


Using point-slope form with slope =4= 4 and point (3,8)(3, 8):

y−8=4(x−3)y - 8 = 4(x - 3)

y−8=4x−12y - 8 = 4x - 12

y=4x−4y = 4x - 4

4x−y−4=04x - y - 4 = 0

Therefore, the equation of the tangent line is 4x−y−4=04x - y - 4 = 0.

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