Quadratic equation Presented by: Abhishek Kumar

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Master table Signs visible in the X/Y's Question Equation Signs of actual values of X or Y Larger Value's Sign, Smaller Value's sign

Example x2 7x 12 0 y2-5y + 6-0 Soln: The signs of X's equation are and +, which means their solution is and . Both negative values. (Refer to the table) The signs of Y's equation are - and +, which means their solution values are and +. Both positive values. Obviously, X's possible values are both negative... And Y's possible values are both positive. Obviously, solution is X < Y

Example: x2 + 21x-32 = 0 y + 7y 12 0 Soln: The question's signs are and -, for both X & Y equations. Which means X and Y's values can be both positive or negative, as per master table... Answer is an instant CND (Can Not Determine. This takes hardly 5 seconds.

Example x2-12x+32 = 0 y-7y 12 0 Soln: The question's symbols are -, which means both values will be positive for each variable, x and y. x2-4x - 8x32 0 x(x-4)-4(x-8) = 0 X=4, X=8 y2-7y + 12=0 y2 -4y -3y+ 12 0 y(y-4)-3(y-4) = 0 Y= 4, Y = 4 So, X >= Y

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Abhishek Kumar

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Anju Sreekumar Sreekumar

8 months ago

thank you sir

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Nandu krishna

10 months ago

This method is very useful and it is very helpfull........but there wil be exceptions r8 sir??.......if in que 2 ch3 if the x is having value of -1 & -2 and y having -2 and -3 or having values like that then the result will be x<=y na??then how can that be CND??please describe sir!!

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Zing Pi

2 years ago

what is the difference between case 2 and case 3? plz explain?

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Rajath Hegde

2 years ago

What if in the Plus(+) and minus(-) case the positive values of both x and y are equal? Is there any way to check that?

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Sonia bishiyar

2 years ago

thanks , its really save our time

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Hari Ashwath

3 years ago

Does this imply that whenever we get any question wherein x and y are both possessing positive(+) and negative(-) values, it Cannot be Determined? Or are we expected to solve it anyway?

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Abhishek Kumar

3 years ago

it will always be can't be determined if x is +ve,-ve and y is also +ve,-ve. Try to solve some questions based on it and you will always get CND in this case.

Hari Ashwath

3 years ago

Thank you so much. Cheers!