*If p = 1 and q = –2 are roots of a quadratic equation, then quadratic equation will be ……………*
1️⃣ x² + 2x –1= 0
2️⃣ x² – x – 2 = 0
3️⃣ x² – 2x + 1= 0
4️⃣ x² + x + 2 = 0
Answers
Given :- if p = 1 and q = –2 are roots of a quadratic equation, then quadratic equation will be ……………*
1️⃣ x² + 2x –1= 0
2️⃣ x² – x – 2 = 0
3️⃣ x² – 2x + 1= 0
4️⃣ x² + x - 2 = 0
Answer :-
given roots of the equation are (1) and (-2)
so,
→ sum of roots = p + q = 1 + (-2) = (-1)
and,
→ product of roots = (p * q) = 1 * (-2) = (-2) .
now, we know that , a quadratic equation can be written as ,
- x² - (sum of roots)x + product of roots = 0
putting values we get,
→ x² - (-1)x + (-2) = 0
→ x² + x - 2 = 0 (Ans.) (option 4)
Learn more :-
*What is the degree of the polynomial of 5x²y + 8xy² +9?*
1️⃣ 9
2️⃣ 5
3️⃣ 8
4️⃣ 3
https://brainly.in/question/39285589?utm_source=android&utm_medium=share&utm_campaign=question
SOLUTION
TO CHOOSE THE CORRECT OPTION
If p = 1 and q = –2 are roots of a quadratic equation, then quadratic equation will be
1. x² + 2x –1= 0
2. x² – x – 2 = 0
3. x² – 2x + 1= 0
4. x² + x - 2 = 0
CONCEPT TO BE IMPLEMENTED
If the roots of a quadratic equation are given then the quadratic equation is
EVALUATION
Here it is given that p = 1 and q = –2 are roots of a quadratic equation
So
Sum of the zeroes = 1 - 2 = - 1
Product of the Zeroes = 1 × ( - 2 ) = - 2
Hence the required Quadratic equation is
FINAL ANSWER
Hence the correct option is
4. x² + x - 2 = 0
━━━━━━━━━━━━━━━━
Learn more from Brainly :-
1. find the equation that formed by increasing each root of 2x²-3x-1=0by 1
https://brainly.in/question/33063519
2. find the equation that formed by squaring each root of the equation x²+3x-2=0
https://brainly.in/question/33064705