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Question
Select the correct option from the given alternatives:
The line y = mx + 1 is a tangent to the parabola y2 = 4x, if m is _______
Options
1
2
3
4
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Solution
1
Explanation;
y2 = 4x
Compare with y2 = 4ax
∴ a = 1
Equation of tangent is
y = mx + 1
Compare with y = `"m"x + "a"/"m"`
∴ `"a"/"m"` = 1
∴ a = m = 1
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