Application of Derivatives
Tangents and Normals
Premium Question
Grade 12
Question:
The equation of the normal to the curve $y^2 = 4x$ at the point $(1, 2)$ is:
(1) $x + y = 3$
(2) $x - y = 3$
(3) $x + y = 1$
(4) $x - y + 1 = 0$
Step-by-Step Solution
Key Concept: Differentiate $y^2 = 4x$ implicitly to find the slope of the tangent at $(1, 2)$, then take the negative reciprocal of that slope for the normal.
The detailed step-by-step mathematical proof is available inside the Mathbee app workspace.
Correct Answer: (1)