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Module DEMO-32-90DEMO-C-32

Quadratic Root Finder

DEMO-C-32 • Programming in C

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Problem Statement

Write a function float findRoot(float a, float b, float c) that returns the larger root of the quadratic equation ax^2 + bx + c = 0.

Assume real roots exist (discriminant >= 0).

Formula: (-b + sqrt(b^2 - 4ac)) / (2a).

Constraints

a != 0, b^2 - 4ac >= 0.

Input Format

Three floats a, b, c.

Output Format

The larger root.

Sample Testcases

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Sample #1
Public sample
Input
1.0 -3.0 2.0
Output
2.000000
Explanation
Roots are 1 and 2. Max is 2.
Sample #2
Public sample
Input
2.0 0.0 -8.0
Output
2.000000
Explanation
2x^2 = 8 -> x^2=4 -> x=2 or -2. Max 2.
Sample #3
Public sample
Input
1.0 -5.0 6.0
Output
3.000000
Explanation
Roots 2, 3. Max 3.

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