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In finding the roots of x^(2) + px + q =...

In finding the roots of `x^(2) + px + q = 0` the coefficient of x was taken as -7 instead of -8 and the roots were 4 and 3 then the correct roots are

A

4, 3

B

2, 4

C

2, 6

D

4, 6

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we need to find the correct roots of the quadratic equation given that the coefficient of \( x \) was incorrectly taken as -7 instead of -8. ### Step 1: Identify the given roots and their properties The roots provided are 4 and 3. We can use these roots to find the values of \( p \) and \( q \) in the quadratic equation \( x^2 + px + q = 0 \). **Hint:** The sum of the roots \( r_1 + r_2 = -p \) and the product of the roots \( r_1 \cdot r_2 = q \). ### Step 2: Calculate the sum and product of the roots - The sum of the roots \( 4 + 3 = 7 \). - The product of the roots \( 4 \cdot 3 = 12 \). Since the coefficient of \( x \) was incorrectly taken as -7, we need to find the correct values: - The correct sum of the roots should be \( -p = -8 \) (as per the problem statement), which gives \( p = -8 \). - The product \( q = 12 \). ### Step 3: Write the correct quadratic equation Using the values of \( p \) and \( q \), we can write the correct quadratic equation: \[ x^2 - 8x + 12 = 0 \] **Hint:** The standard form of a quadratic equation is \( ax^2 + bx + c = 0 \). ### Step 4: Factor the quadratic equation Now, we need to factor the equation \( x^2 - 8x + 12 = 0 \): \[ x^2 - 8x + 12 = (x - 6)(x - 2) = 0 \] **Hint:** To factor, look for two numbers that multiply to \( c \) (12) and add to \( b \) (-8). ### Step 5: Find the roots Setting each factor equal to zero gives us the roots: 1. \( x - 6 = 0 \) → \( x = 6 \) 2. \( x - 2 = 0 \) → \( x = 2 \) Thus, the correct roots of the equation are \( 6 \) and \( 2 \). ### Final Answer The correct roots are **2 and 6**.
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