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MathsHardMCQ2018 ยท 16 Apr Online

Q70.Let P be a point on the parabola x2 = 4y. If the distance of P from the center of the circle x2 + y2 + 6x + 8 = 0 is minimum, then the equation of the tangent to the parabola at P is (1) x + y + 1 = 0 (2) x + 4y โˆ’2 = 0 (3) x + 2y = 0 (4) x โˆ’y + 3 = 0

What This Question Tests

This question integrates concepts from parabolas (point on parabola, tangent) and circles (center, distance) along with calculus (minimizing distance using differentiation), making it a multi-concept and challenging problem.

Concepts Tested

Equation of parabolaDistance formulaMinimization using derivativesEquation of tangent to parabola

Formulas Used

Distance formula = sqrt((x2-x1)^2 + (y2-y1)^2)

Equation of tangent to y^2=4ax at (x1,y1) is yy1=2a(x+x1)

Equation of tangent to x^2=4ay at (x1,y1) is xx1=2a(y+y1)

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