TI-Nspire Finance Functions

The TI-Nspire calculator provides several built-in finance functions that simplify financial calculations. These functions are accessible through the Finance Solver or individual commands, enabling users to analyze investments, loans, and other financial scenarios.

Accessing the Finance Solver

The Finance Solver is a dedicated interface for solving time-value-of-money (TVM) problems. To access it, navigate to: Menu > Finance > Finance Solver. The solver presents a table with fields for the following variables:

• N: Total number of compounding periods.
• I%: Annual interest rate (entered as a percentage).
• PV: Present value of the investment or loan.
• PMT: Payment amount per period.
• FV: Future value of the investment or loan.
• PpY: Payments per year.
• CpY: Compounding periods per year.
• PMT: BEGIN/END: Indicates whether payments are made at the beginning or end of the period.

To solve for a particular variable, enter the known values into the corresponding fields, place the cursor on the field you want to solve for, and press Enter. The calculator will calculate and display the solution.

Individual Finance Commands

Besides the Finance Solver, the TI-Nspire also offers individual finance commands accessible directly from the calculation screen. These commands offer more flexibility for complex calculations and can be incorporated into programs. Some commonly used commands include:

• tvmFV(N, I%, PV, PMT, PpY, CpY): Calculates the future value of an investment.
• tvmPV(N, I%, PMT, FV, PpY, CpY): Calculates the present value of an investment.
• tvmPMT(N, I%, PV, FV, PpY, CpY): Calculates the payment amount per period.
• tvmI%(N, PV, PMT, FV, PpY, CpY): Calculates the annual interest rate.
• tvmN(I%, PV, PMT, FV, PpY, CpY): Calculates the number of compounding periods.
• irr(CF0, CFList, CFFreq): Calculates the internal rate of return (IRR) for a series of cash flows. CF0 is the initial cash flow, CFList is a list of subsequent cash flows, and CFFreq is a list of the frequencies of those cash flows.
• npv(I%, CF0, CFList, CFFreq): Calculates the net present value (NPV) for a series of cash flows. I% is the discount rate.

Important Considerations

• Sign Conventions: Ensure you use consistent sign conventions. Generally, cash inflows are positive and cash outflows are negative.
• Interest Rate Format: Enter the interest rate as a percentage (e.g., 5 for 5%).
• Compounding Frequency: Ensure that the compounding frequency (CpY) matches the payment frequency (PpY) unless otherwise specified.
• Begin/End Mode: Correctly specify whether payments are made at the beginning or end of the period, especially for annuities due.

By understanding and utilizing these finance functions, users can effectively analyze financial scenarios, make informed investment decisions, and solve complex financial problems using their TI-Nspire calculator.