if roots of the equation (a-b)x²+(b-c)x +(c-a) =0 are equal then b+c=
Answers
EXPLANATION.
Roots of the equation,
f(x) = ( a - b)² + ( b - c)x + ( c - a ) = 0.
To Find the value of b + c.
As we know that,
D = b² - 4ac.
⇒ (b - c)² - 4(a - b)(c - a) = 0.
⇒ b² + c² - 2bc - 4 [ac - a² - bc + ab] = 0.
⇒ b² + c² - 2bc - 4ac + 4a² + 4bc - 4ab = 0.
⇒ b² + c² + 2bc + 2a² - 4ac - 4ab = 0.
⇒ (2a - b - c )² = 0.
⇒ 2a = b + c.
Value of b + c = 2a.
MORE INFORMATION.
Quadratic equation.
A polynomial of degree two of the form ax² + bx + c ( a ≠ 0) is called a quadratic expression in x.
The Quadratic Equation,
ax² + bx + c = 0. ( a ≠ 0 ) has two roots,
⇒ α = -b + √b² - 4ac/2a
⇒ β = -b - √b² - 4ac/2a.
Sum of Roots.
The Quadratic Equation whose roots are α,β.
Sum of zeroes of quadratic equation.
⇒ α + β = -b/a.
Products of zeroes of quadratic equation.
⇒ αβ = c/a.
Quadratic equation ⇒ x² - ( α + β)x + αβ.
Hi,
We know that,
If the quadratic equation ax²+bx+c=0
whose roots are equal then it's
deteminant is equal to zero.
(a-b)x²+(b-c)x+(c-a)=0
Deteminant =0
(b-c)² -4(a-b)(c-a)==0
b²+c²-2bc-4ac+4a²+4bc-4ab=0
b²+c²+4a²+4bc-4ac-4ab=0
b²+c²+(-2a)²+2bc+2c(-2a)+2(-2a)b=0
(b+c-2a)²=0
b+c-2a=0
Therefore,
b+c=2a
Hence proved.
:)