<span>The answer is <span>in the file</span></span>
I would go with the first two because the first one is true but the last two are false for a fact so the second answer would have to be the second check box
I have a solution here that has a slight change in given where instead of <span>(4, 32), it is (3, 18). However, since the solution has provided explanations on each process, step-by-step, I believe that by thoroughly analyzing it, you might just answer this problem on your own!
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f(x) = 2x² ← this is the parabola
f(3) = 2 * 9 = 18 → the parabola passes through A (3 ; 18), so its tangent line too
f'(x) = 4x ← this is the derivative
…and the derivative is the slope of the tangent line to the curve at x
f'(3) = 4 * 3 = 12 ← this is the slope of the tangent line to the curve at x = 3
Equation of the tangent line
The typical equation of a line is: y = mx + b → where m: slope and where b: y-intercept
You know that the slope of the tangent line is 12.
The equation of the tangent line becomes: y = 12x + b
The tangent line passes through A (3 ; 18), so these coordinates must verify the equation of the tangent line.
y = 12x + b
b = y - 12x → you substitute x and y by the coordinates of the point A (3 ; 18)
b = 18 - 36 = - 18
→ The equation of the tangent line is: y = 12x - 18
Intersection between the tangent line to the curve and the x-axis: → when y = 0
y = 12x - 18 → when y = 0
12x - 18 = 0
12x = 18
x = 3/2
→ Point B (3/2 ; 0)
Intersection between the vertical line passes through the point A and the x-axis: → when x = 3
→ Point C (3 ; 0)
The equation of the vertical line is: x = 3
Area of the region bounded by the parabola y = 2x², the tangent line to this parabola at (3 ; 18), and the x-axis.
= (area of the region bounded by the parabola y = 2x² and the x-axis) - (area of the triangle ABC)
= [∫ (from 0 to 3) of the parabola] - [(xC - xB).(yA - yC)/2]
= [∫ (from 0 to 3) 2x².dx] - [(xC - xB).(yA - yC)/2]
= { [(2/3).x³] from 0 to 3 } - { [3 - (3/2)].(18 - 0)/2 }
= [(2/3) * 3³] - { [(6/2) - (3/2)] * 9 }
= [(2/3) * 27] - { [(3/2) * 9 }
= 18 - (27/2)
= (36/2) - (27/2)
= 9/2 square unit
ANSWER
(-1,2)
EXPLANATION
The given quadratic expression is:
The coefficient of the quadratic term is already 1.
So we add and subtract the square of half the coefficient of x.
We factor the first three terms to obtain
This is now in the form:
where (h,k) which is equal to (-1,2) is the vertex.
