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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Ravi Rajput

2 years ago

Differences between Formal & Informal Sectors in India: formal sector as activities which are taxed and monitored by the government and the activities involved are included in the Gross Domestic Product(GDP). In contrast to formal economy is the informal sector which is neither taxed nor included in the GDP and Gross national product (GNP) of a country.

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Hungry Lion

2 years ago

can u explain why not include in gdp in the case of informal

Ravi Rajput

2 years ago

The informal sector, informal economy, or grey economy is the part of an economy that is neither taxed, nor monitored by any form of government. Unlike the formal economy, activities of the informal economy are not included in the gross national product (GNP) and gross domestic product (GDP) of a country.

Hungry Lion

2 years ago

if a carpenter make a table sold to any furniture shop govt charged gst on value addition
how can u say that informal sector is not taxed

Chandra Acharya

2 years ago

what is tge diff between unformal and unorganised sector ? are both same ?

Chandra Acharya

2 years ago

*informal and unorganised

Hungry Lion

2 years ago

unorganised sector take account in gdp but informal cant

Chandra Acharya

2 years ago

thank you !

Nandu krishna

a year 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!