Engineering Board Exam Reviewer · Parabolas · medium
Find the equation of the tangent line to the parabola y2=8x at the point (2,4).
- x + y - 6 = 0
- x - y - 2 = 0
- x - y + 2 = 0
- 2 x - y = 0
Answer
C. x - y + 2 = 0
Solution
Implicit differentiation: 2y,y'=8 y'= 4y=1 at (2,4). y-4=x-2 x-y+2=0.
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