SOLUTION: The curve y = x^2 - 3x + 4 passes through the points P(1,2) and Q(3,4). Find a) the equation of tangent at P b) the equation of the normal at Q

Algebra.Com
Question 1202600: The curve y = x^2 - 3x + 4 passes through the points P(1,2) and Q(3,4). Find
a) the equation of tangent at P
b) the equation of the normal at Q

Answer by ikleyn(52776)   (Show Source): You can put this solution on YOUR website!
.
The curve y = x^2 - 3x + 4 passes through the points P(1,2) and Q(3,4). Find
(a) the equation of tangent at P
(b) the equation of the normal at Q
~~~~~~~~~~~~~~~~~

(a)  Take the derivative.   It is  y' = 2x - 3.

     Calculate the value of the derivative at P(1,2).  It is

         y'(1) = 2*1 - 3 = 2 - 3 = -1.


     Hence, the slope of the tangent line at P is -1.

     So, the tangent line at  P(1,2)  is  

         y-2 = (-1)*(x-1),  (1)

     or any other equivalent form.



(b)  Calculate the value of the derivative at Q(3,4).  It is

         y'(3) = 2*3 - 4 = 6 - 4 = 2.


    Hence, the slope of the tangent line at Q is 2.

    Therefore, the slope of the normal to the curve at Q is  = -0.5.

    Thus the normal to the curve at  Q(3,4)  is

        y-4 = -0.5(x-3)

    or any other equivalent form.

Solved.



RELATED QUESTIONS

In a figure, curve A whose equation is y=(x+a)^2, passes through the point (4,0). Curve... (answered by Boreal)
1. Find the possible values of the constant m, for which the curve (m+5)x² + (m²- 1)y²... (answered by ikleyn)
A line tangent to the curve x = y^(1/2) at the point P intersects the x axis at the... (answered by Edwin McCravy,robertb)
Find the equation of the tangent to the curve y= [4/(x^2)]+1 at the point where x=a. This (answered by Fombitz)
Find the equation of the tangent to the curve y=x+x^2 at the point where x=a find the... (answered by ikleyn,greenestamps)
1) Find the exact solution of the equation: 32/e^x - e^2x = 4 2) A... (answered by solver91311)
The graph of the function y=-x^2 + px + 11 has a tangent when x=2. The tangent passes... (answered by robertb)
Find the slope of the line through the points P and Q when: a. P(1,3) and Q(x,... (answered by math_helper)
Find the slope of the line through the points P and Q when: a. P(1,3) and Q(x,... (answered by MathLover1,rothauserc)