One of the roots of the quadratic equation x2−5mx+6m2=0 is 36. Find the greatest possible value of the second root. Help needed as soon as possible, Thank You.

Respuesta :

The greatest possible value of the second root, β = 54

Step-by-step explanation:

The given quadratic equation:

[tex]x^2-5mx+6m^2=0[/tex]

Let α and β be the roots of the given quadratic equation.

α = 36

To find,  the greatest possible value of the second root ( β) = ?

∴ The sum of the roots,

α + β = [tex]\dfrac{-b}{a}[/tex]

⇒ 36 + β = [tex]\dfrac{-(-5m)}{1}[/tex]

⇒ 5m = 36 + β               ............. (1)

The product of the roots,

α.β = [tex]\dfrac{c}{a}[/tex]

⇒ [tex]36.\beta=\dfrac{6m^2}{1}[/tex]

⇒ [tex]6.\beta=m^2[/tex]                   ............. (2)        

From equations (1) and (2), we get  

⇒ [tex](\dfrac{36+\beta}{5})^{2}=6\beta[/tex]

⇒ [tex]\beta^2-78\beta+1296=0[/tex]

⇒ [tex]\beta^2-54B\beta-24B\beta+1296=0[/tex]

⇒ β(β - 54) - 24(β - 54) = 0

⇒ (β - 54)(β - 24) = 0

⇒ β - 54 = 0 or, β - 24 = 0

⇒ β = 54 or, β = 24

∴  The greatest possible value of the second root, β = 54