alpha and beta are the zeros of the polynomial 2 x square - 4 x + 5 find the value of bracket Alpha minus beta whole square
Answers
ANSWER:
- Value of (α-β)² is (-6)
GIVEN:
- α and β are the Zeros of the quadratic polynomial 2x²-4x+5.
TO FIND:
- (α-β)²
SOLUTION:
Formula
=> (α+β) = -(coefficient of x)/coefficient of x²
=> αβ = Constant term/coefficient of x²
=> (α-β)² = (α+β)²-4αβ ....(i)
P(x) = 2x²-4x+5
=> α+β = -(-4)/2
=> α+β = 2
=>αβ = 5/2
Putting these value in eq(i) we get;
=> (α-β)²= (2)²-4(5/2)
=> (α-β)²= 4-10
=> (α-β)²= (-6)
Value of (α-β)² is (-6)
NOTE:
Some important formulas:
(a+b)² = a²+b²+2ab
(a-b)² = a²+b²-2ab
(a+b)² = (a-b)²+4ab
(a-b)² = (a+b)²-4ab
GIVEN:
α and β are the two zeroes of polynomial 2x² - 4x + 5
TO FIND:
The value of (α-β)²
SOLUTION:
We know that,
Sum of zeroes of polynomial = α + β = -b/a
Product of zeroes = αβ = c/a
(a - b)² = (a + b)² - 4ab
In the above polynomial,
a = 2 ; b = -4 and c = 5
Now,
Sum of zeroes = α + β = -(-4)/2 = 1
Product of zeroes = αβ = 5/2
(α - β)² = (α + β)² - 4αβ
= (2)² - 4(5/2)
= 4 - 10
= -6
Therefore, the value of (α - β)² is -6.