if x and B are the zeros of a polynomial such that X + Y is equal to 5 x b is equal to 4 then write the polynomial
Answers
Step-by-step explanation:
Correct Question :-
- If α and β are the zeroes of a polynomial such that α + β = 5 and αβ = 4
Solution :-
Given -
α + β = 5
αβ = 4
To Find -
- Write the polynomial
As we know that :-
- α + β = -b/a
→ 5/1 = -b/a ...... (i)
And
- αβ = c/a
→ 4/1 = c/a ........ (ii)
Now, From (i) and (ii), we get :
a = 1
b = -5
c = 4
As we know that :-
For a quadratic polynomial :-
- ax² + bx + c
→ (1)x² + (-5)x + (4)
→ x² - 5x + 4
Hence,
The polynomial is x² - 5x + 4
Verification :-
- α + β = -b/a
→ 5 = -(-5)/1
→ 5 = 5
LHS = RHS
And
- αβ = c/a
→ -4 = -4/1
→ -4 = -4
LHS = RHS
Hence,
Verified...
It shows that our answer is absolutely correct.
✰ sum of zeroes = 5
✰ product of zeroes = 4
✰ we need to find the polynomial
let α and β are the zeroes of required polynomial.
So,
α + β = 5
αβ = 4
p(x) = x² - (α + β)x + αβ
x² -(5)x + 4
x² - 5x +4 = 0
Hence the required polynomial is
⠀⠀⠀⠀=⠀x² - 5x +4 = 0
Now varification:-
α + β = - b/a
αβ = c/a
sum of zeroes :-
5 = -(-5)/1
5 = 5
Now product of zeroes:-
4 =4/1
4 = 4
LHS = RHS
hence varified.
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