Casio fx-CG50 for Further Maths
Not a computer algebra system. Model and OS matter; a graph may hide roots or discontinuities outside the viewing window.
Complex numbers with the fx-CG50
The CG50 was discontinued in September 2025; many students still use it. Exam mode and permitted resources depend on the paper.
Find both intersections of a line and curve
Find the intersections of y = x² and y = x + 2.
- Open Graph from the main menu. Enter x² in Y1 and x + 2 in Y2 and enable both.
- Draw the graphs with a window containing x from −3 to 3 and y from −1 to 6.
- Open G-Solv and choose INTSECT. If prompted, select the two graphs.
- Use the right arrow to move to the next intersection and record its coordinates too.
Expected result: The intersections are (−1,1) and (2,4).
Solve x² = x + 2 algebraically: (x − 2)(x + 1) = 0. Substitute into either function to recover the paired y-values.
An intersection outside the window may be missed. A numerical graph reading does not establish exact coordinates by itself. These steps are for CG50; CG100 uses different menus.
Before accepting an answer
Check angle mode, domain and the form requested. A decimal approximation does not replace an exact result, and a list of numerical roots does not show why every required root has been found.
For matrix work, confirm dimensions and multiplication order. For a probability, choose the tail and interpret it in context before deciding what the result means.
Use the linked manufacturer instructions for the exact screen and software version. Menu names differ between models.