Questions: Find the value of (p) for which the quadratic equation (p x^2-4 p x+2-p=0) has equal roots
Transcript text: of possible values of $k$.
Find the value of $p$ for which the quadratic equation $p x^{2}-4 p x+2-p=0$ has equal roots
Solution
Solution Steps
To find the value of \( p \) for which the quadratic equation \( p x^{2} - 4 p x + 2 - p = 0 \) has equal roots, we need to use the condition for equal roots in a quadratic equation. The condition is that the discriminant (\( \Delta \)) must be zero. The discriminant for a quadratic equation \( ax^2 + bx + c = 0 \) is given by \( \Delta = b^2 - 4ac \). We will set this discriminant to zero and solve for \( p \).
Step 1: Identify the Quadratic Equation
Given the quadratic equation:
\[ p x^{2} - 4 p x + 2 - p = 0 \]
Step 2: Determine the Discriminant
For a quadratic equation \( ax^2 + bx + c = 0 \), the discriminant \( \Delta \) is given by:
\[ \Delta = b^2 - 4ac \]
Here, \( a = p \), \( b = -4p \), and \( c = 2 - p \). Substituting these values, we get:
\[ \Delta = (-4p)^2 - 4(p)(2 - p) \]
\[ \Delta = 16p^2 - 4p(2 - p) \]
\[ \Delta = 16p^2 - 8p + 4p^2 \]
\[ \Delta = 20p^2 - 8p \]
Step 3: Set the Discriminant to Zero
For the quadratic equation to have equal roots, the discriminant must be zero:
\[ 20p^2 - 8p = 0 \]
Step 4: Solve for \( p \)
Factor the equation:
\[ 4p(5p - 2) = 0 \]
Setting each factor to zero gives:
\[ 4p = 0 \quad \text{or} \quad 5p - 2 = 0 \]
\[ p = 0 \quad \text{or} \quad p = \frac{2}{5} \]