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Given a quadratic equation px²+px+3q=1+2x has the roots 1/p and qfind the value of p and q

User Warkolm
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1 Answer

3 votes

Solution:

The given equation is:


px^2+px+3q\text{ = 1+2x}

We can write it as:


px^2+px+3q\text{ - 1-2x}=0

Rearrange the terms, we get:


px^2-2x+px+(3q-1)=0

This can be written as:


px^2+x(p-2)+(3q-1)=0

Now wrt Standard form of a quadratic equation:


ax^2+bx+c=0

we have:


a\text{ =p}


b=p-2

and


c\text{ = }3q-1

We know that product of zeroes :


q\text{ x }(1)/(p)=(3q-1)/(p)

then


3q-1=q

then


2q\text{ = 1}

so that,


q\text{ =}(1)/(2)

Sum of roots :


q+(1)/(p)=(2-p)/(p)

then


(qp+1)/(p)=(2-p)/(p)

then


qp+1\text{ = 2-p}

then


(p)/(2)+p=1

solving for p, we get:


p\text{ = }(2)/(3)

so that, we can conclude that the correct answer is:


p\text{ = }(2)/(3)

and


q\text{ =}(1)/(2)

User SnNaCk
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