GDC Lab

Calculator setup

Degrees vs radians

Read the angle unit in the question before calculating. Use radians for calculus with trigonometric functions unless the problem explicitly uses degrees. Estimate the sign and size first, then check that the display mode agrees.

Graphing functions

Enter each function with brackets that preserve its structure. Choose a window from the mathematical context, then identify features rather than trusting the first picture.

Roots / zeros

Graph the function, bracket the root and use a zero or solve operation. Report the coordinate or value to the precision requested and verify it in the original equation.

Intersections

Graph both functions in the same window. Select the relevant intersection, record both coordinates and state which equation or model the point solves.

Maximum and minimum

Use the graph to bracket a turning point before applying a maximum or minimum command. Explain what the coordinates mean in the problem context.

Numerical derivatives

Enter the function and the evaluation point carefully. A numerical derivative gives an approximation, so retain calculator precision before rounding the final gradient.

Numerical integrals

Write the definite integral first, including limits. Use a numerical integral for its value, then decide whether the signed result or a positive geometric area is required.

One-variable statistics

Place raw data or values and frequencies in separate lists. Check the list lengths, then interpret the mean, quartiles and standard deviation with units.

Regression

Identify the explanatory and response variables before entering data. Choose the requested model, record its parameters and use extrapolation only with a clear warning.

Binomial distribution

Define the random variable and write its binomial model. Decide whether the event needs a single probability or a cumulative probability before entering n, p and bounds.

Normal CDF

Write the normal model and the probability statement first. Convert words into lower and upper bounds, then use the cumulative area and check that the probability lies between 0 and 1.

Inverse normal

Use inverse normal when an area is known and a boundary value is unknown. Sketch the tail, convert it to a left-tail area if needed and label the resulting value.

Tables

A table can reveal sign changes, convergence and repeated values. Choose a sensible start and step, then use the pattern as evidence rather than as a substitute for proof.

Euler's method

Record the initial point and step size. Repeatedly evaluate the derivative, update y and advance x; keep unrounded values so rounding error does not accumulate unnecessarily.