Home
Class 12
MATHS
If quadratic equation ax^(2) + bx + ab +...

If quadratic equation `ax^(2) + bx + ab + bc + ca - a^(2) - b^(2) - c^(2) = 0` where `a, b, c` distinct reals, has imaginary roots than (A) `a+b+ab+bc+calta^(2)+b^(2)+c^(2)` (B)`a-b+ab+bc+cagta^(2)+b^(2)+c^(2)` (C)`4a+2b+ab+bc+calta^(2)+b^(2)+c^(2)` (D)`2(a+-3b)-9{(a-b)^(2)+(b-c)^(2)+(c-a)^(2)}lt0`

A

`a+b+ab+bc+calta^(2)+b^(2)+c^(2)`

B

`a-b+ab+bc+cagta^(2)+b^(2)+c^(2)`

C

`4a+2b+ab+bc+calta^(2)+b^(2)+c^(2)`

D

`2(a+-3b)-9{(a-b)^(2)+(b-c)^(2)+(c-a)^(2)}lt0`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the quadratic equation \( ax^2 + bx + ab + bc + ca - a^2 - b^2 - c^2 = 0 \) and determine the conditions under which it has imaginary roots, we will follow these steps: ### Step 1: Identify the quadratic equation The given quadratic equation is: \[ ax^2 + bx + (ab + bc + ca - a^2 - b^2 - c^2) = 0 \] ### Step 2: Determine the discriminant For a quadratic equation \( Ax^2 + Bx + C = 0 \), the roots are imaginary if the discriminant \( D = B^2 - 4AC < 0 \). Here, we identify: - \( A = a \) - \( B = b \) - \( C = ab + bc + ca - a^2 - b^2 - c^2 \) Thus, the discriminant \( D \) is: \[ D = b^2 - 4a(ab + bc + ca - a^2 - b^2 - c^2) \] ### Step 3: Simplify the discriminant We need to simplify the expression for \( D \): \[ D = b^2 - 4a(ab + bc + ca - a^2 - b^2 - c^2) \] Expanding this gives: \[ D = b^2 - 4a(ab) - 4a(bc) - 4a(ca) + 4a(a^2) + 4a(b^2) + 4a(c^2) \] \[ D = b^2 - 4a^2 + 4ab^2 + 4ac^2 - 4abc - 4abc \] ### Step 4: Set the discriminant less than zero To find the conditions for imaginary roots, we set \( D < 0 \): \[ b^2 - 4a(ab + bc + ca - a^2 - b^2 - c^2) < 0 \] ### Step 5: Analyze the options Now we will analyze the provided options to see which one satisfies the condition \( D < 0 \). 1. **Option A**: \( a + b + ab + bc + ca < a^2 + b^2 + c^2 \) 2. **Option B**: \( a - b + ab + bc + ca < a^2 + b^2 + c^2 \) 3. **Option C**: \( 4a + 2b + ab + bc + ca < a^2 + b^2 + c^2 \) 4. **Option D**: \( 2(a - 3b) - 9((a-b)^2 + (b-c)^2 + (c-a)^2) < 0 \) ### Step 6: Determine which options are valid - **Option A**: This condition can be derived from the discriminant analysis. - **Option B**: This condition is not necessarily true as it can be greater than \( a^2 + b^2 + c^2 \). - **Option C**: This condition can also be derived from the discriminant analysis. - **Option D**: This condition can be valid under certain circumstances. ### Conclusion The options that satisfy the condition for imaginary roots are: - **Option A** - **Option C** - **Option D**

To solve the quadratic equation \( ax^2 + bx + ab + bc + ca - a^2 - b^2 - c^2 = 0 \) and determine the conditions under which it has imaginary roots, we will follow these steps: ### Step 1: Identify the quadratic equation The given quadratic equation is: \[ ax^2 + bx + (ab + bc + ca - a^2 - b^2 - c^2) = 0 \] ...
Promotional Banner

Topper's Solved these Questions

  • TEST PAPERS

    RESONANCE ENGLISH|Exercise PART - I MATHEMATICS SEC - 2|1 Videos
  • TEST PAPERS

    RESONANCE ENGLISH|Exercise PART - I MATHMATICS|84 Videos
  • TEST PAPERS

    RESONANCE ENGLISH|Exercise PART : 1MATHEMATICS SEC - 2|10 Videos
  • TEST PAPER

    RESONANCE ENGLISH|Exercise MATHEMATICS|48 Videos
  • TEST SERIES

    RESONANCE ENGLISH|Exercise MATHEMATICS|132 Videos

Similar Questions

Explore conceptually related problems

If a + b- c = 4 and a^(2) + b^(2) + c^(2)= 38 , find ab- bc - ca

If a + b + c= 12 and a^(2) + b^(2) + c^(2) = 50 , find ab + bc + ca

If a+b+ c =9 and a^(2) + b^(2) + c^(2) = 29 , find ab + bc + ca .

If a + b+ c= p and ab + bc + ca= q , find a^(2) +b^(2) + c^(2)

If a+b+c = 10 and a^(2) + b^(2) + c^(2) = 38 , find : ab + bc + ca

If a+b+c =11 and a^(2) + b^(2) + c^(2) =81 , find : ab + bc + ca .

If a-b-c= 3 and a^(2) + b^(2) + c^(2) = 77 , find: ab- bc+ ca

If a^(2) + b^(2) + c^(2) = 50 and ab +bc + ca= 47 , find a + b+ c

Find : a + b+ c , if a^(2) + b^(2) + c^(2) = 83 and ab + bc + ca = 71 .

If a^(2) + b^(2) + c^(2) = 35 and ab+ bc + ca= 23 , find a + b+ c