JEE Main 2020MathematicsApplication of DerivativesMediumNumerical

JEE Main 2020 — Application of Derivatives Question with Solution

JEE Main 2020 (05 Sep Shift 2)

Question

If the lines x+y=a and x-y=b touch the curve y=x2-3x+2 at the points where the curve intersects the x-axis, then ab is equal to …

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Show full solutionCorrect answer: 0.5
Correct answer
0.5

Step-by-step explanation

y=x2-3x+2,  x+y=a,x-y=b

⇒x2-3x+2=0

x1=2  x2=1

Therefore, points are(2,0) (1,0)

b=2  a=1

∴ab=12=0.5

 

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About this question

This is a previous-year question from JEE Main 2020, covering the Application of Derivatives chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.