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If both roots are less than 3 then 'a' b...

If both roots are less than 3 then 'a' belongs to

A

`((3)/(2),3)`

B

`(-1,2)cup(2,3)`

C

`(-infty,2)`

D

`(2,infty)`

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The correct Answer is:
To solve the problem, we need to analyze the given quadratic equation and determine the conditions under which both roots are less than 3. Let's denote the quadratic equation as: \[ ax^2 + bx + c = 0 \] ### Step 1: Identify the conditions for the roots For a quadratic equation \( ax^2 + bx + c = 0 \), the roots can be found using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] To ensure that both roots are less than 3, we need to satisfy two conditions: 1. The sum of the roots \( \frac{-b}{a} < 6 \) (since \( 3 + 3 = 6 \)) 2. The product of the roots \( \frac{c}{a} < 9 \) (since \( 3 \times 3 = 9 \)) ### Step 2: Apply the conditions to the coefficients Let’s denote the coefficients of the quadratic equation as follows: - \( a = 1 \) - \( b = -6 \) (from the sum condition) - \( c = 9 \) (from the product condition) ### Step 3: Set up the inequalities From the conditions derived, we can set up the following inequalities: 1. \( -\frac{b}{a} < 6 \) implies \( -b < 6a \) 2. \( \frac{c}{a} < 9 \) implies \( c < 9a \) ### Step 4: Solve the inequalities Substituting the values of \( a \), \( b \), and \( c \): 1. For \( -b < 6a \): - If \( b < 0 \), then \( -b > 0 \) and the inequality holds. 2. For \( c < 9a \): - If \( c < 9 \), then this condition is satisfied. ### Step 5: Conclusion Thus, for both roots to be less than 3, we find that \( a \) must belong to a specific range. ### Final Answer The values of \( a \) that satisfy both conditions are those for which the inequalities hold true.
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