What is the equation of the tangent lines of #f(x) =-x^2+8x-4/x# at # f(x)=0#?

Answer 1

Do the rest calculations

Assigned role:

#f(x)=-x^2+8x-4/x#
#f'(x)=-2x+8+4/x^2#
Now, setting #f(x)=0#, we get
#-x^2+8x-4/x=0#
#\frac{-x^3+8x^2-4}{x}=0#
#x^3-8x^2+4=0\ \quad (x\ne 0)#

When we solve the aforementioned equations, we obtain

#x=-0.679, 0.742, 7.936#

Thus, the locations of the drawn tangents are

#(-0.679, 0)#, #(0.742, 0)# & #(7.936, 0)#

Now, by determining the slopes at each of the three points above, one can determine the equations of the tangents at those locations.

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Answer 2

To find the equation of the tangent lines of f(x) = (-x^2 + 8x - 4)/x at f(x) = 0, we need to determine the derivative of the function and substitute the x-value where f(x) = 0 into the derivative. The derivative of f(x) is given by f'(x) = (2x^2 - 8x + 4)/x^2.

To find the x-value where f(x) = 0, we set the numerator of the function equal to zero: -x^2 + 8x - 4 = 0. Solving this quadratic equation, we find x = 2 ± √3.

Now, we substitute these x-values into the derivative f'(x) to find the slopes of the tangent lines. When x = 2 + √3, f'(x) = (2(2 + √3)^2 - 8(2 + √3) + 4)/(2 + √3)^2. Simplifying this expression, we get f'(x) = 2 + √3.

Similarly, when x = 2 - √3, f'(x) = (2(2 - √3)^2 - 8(2 - √3) + 4)/(2 - √3)^2. Simplifying this expression, we get f'(x) = 2 - √3.

Therefore, the equations of the tangent lines at f(x) = 0 are y = (2 + √3)(x - (2 + √3)) and y = (2 - √3)(x - (2 - √3)).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

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