Given a quadratic function with respect to . takes the values of and for the values of respectively.
Find the length of the line segment of the graph of the curve cut by the -axis.
1956 Tokyo Institute of Technology entrance exam
Given a quadratic function with respect to . takes the values of and for the values of respectively.
Find the length of the line segment of the graph of the curve cut by the -axis.
1956 Tokyo Institute of Technology entrance exam
1. Determine the quadratic function:
Given the values of for specific values, we can set up a system of equations to find the coefficients of the quadratic function .
- For , :
- For , :
- For , :
2. Solve the system of equations:
Substitute from Equation 2 into Equations 1 and 3:
- Equation 1:
- Equation 3:
Add Equations 4 and 5 to eliminate :
Substitute back into Equation 4:
Therefore, the quadratic function is:
3. Find the roots of the quadratic function:
To find where the curve cuts the -axis, set :
Use the quadratic formula :
4. Calculate the distance between the roots:
The roots are and .
The distance between the roots is:
The final answer is .