Product of roots of x^2+8x+5
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Product of roots of x^2+8x+5

Solution:- Let F(x)=x^2+8x+5

We know that αβ = c/a

                               =5/1

                               =5

If α and β are roots of the equation x2+8x−5=0, then what is the quadratic equation whose roots are α/β and β/α?

Solution
Given equation is x^2+8x−5=0
α + β=-8
αβ=-5
We have to find the new Quadratic equation using this root α/β and β/α.
now sum of roots of new Quadratic Equation
 α/β +β/α
 =(α^2 + β^2)/αβ
=(α+β)^2/αβ
= (-8)^2/-5
=-64/5 
product of roots
=(α/β)(β/α)
= 1
=5/5
here a=5,b=-64,c=5
we know that the standard form of Quadratic Equation
ax^2 +bx +c=0 
5x^2 +(-64)x +5=0 
5x^2 - 64x +5=0 
the new Quadratic equation 5x^2 - 64x +5=0 .
 
  If α and β are roots of equation x^2+5x+5=0 then write quadratic equation whose roots are α +1 and  β+1.

 Solution
Given equation is x^2+5x+5=0
α + β=-b/a=-5/1=-5
αβ=c/a=5/1=5
We have to find the new Quadratic equation using this root α/β and β/α.
now sum of roots of new Quadratic Equation
α +1 + β+1
 =α+β+2
=-5+2
=-3
product of roots
=(α +1)(β+1)
=αβ+ +β)+1
=5-5+1
 =1
here a=1,b=-3,c=1
we know that the standard form of Quadratic Equation
ax^2 +bx +c=0 
1x^2 +(-3)x+1=0 
x^2 -3x +1=0 
the new Quadratic equation x^2 -3x +1=0 
 
Q.The roots α and β of the quadratic equation x^2 - 5x + 3(k - 1) = 0 are such that αβ = 1. Find the value k.
   Solution
Given equation is x^2 - 5x + 3(k - 1) = 0
and αβ = 1
using formula,
c/a=1
3(k - 1)/1=1
k - 1=1/3
k =1/3+1
k=(1+3)/3
k=4/3 Ans
 
The roots α  and β  of the quadratic equation x2−5x+3(k−1)=0  are such that α−β=11 Find the value of k.  
 
 
 
 
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