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TI-84 program examples, simplest to hardest.

Five real TI-84 programs that run right here, on the same pixel-LCD screen the app uses. Press run and answer the prompts yourself.

The first three are things any E-Code account already does. The last two are the upper-level kind that Pro unlocks, shown here so you can see the difference.

Formula reference card

AlgebraFree

What you’d ask“Give me a quick formula card for the quadratic formula, the slope formula, and the distance formula — something I can flip through with a menu during practice.”

The codeFORMULAS.8xp

Lbl 0
Menu("FORMULA CARD","QUADRATIC",1,"SLOPE",2,"DISTANCE",3,"DONE",4)
Lbl 1
"//QUADRATIC FORMULA: SOLVES AX²+BX+C=0 FOR X"
ClrHome
Disp "QUADRATIC:","X=(-B+-√(B²","-4AC))/(2A)"
Pause 
Goto 0
Lbl 2
"//SLOPE FORMULA: RATE OF CHANGE BETWEEN TWO POINTS"
ClrHome
Disp "SLOPE:","M=(Y2-Y1)/","(X2-X1)"
Pause 
Goto 0
Lbl 3
"//DISTANCE FORMULA: FROM THE PYTHAGOREAN THEOREM"
ClrHome
Disp "DISTANCE:","D=√((X2-X1)²","+(Y2-Y1)²)"
Pause 
Goto 0
Lbl 4
ClrHome
Disp "STUDY WELL!"

The screenTry it yourself

Press run to power on the screen and step through the program.

Pick QUADRATIC, read it, then DONE.

Law of Cosines solver

TrigonometryFree

What you’d ask“Take two sides of a triangle and the angle between them, then find the third side with the Law of Cosines.”

The codeLAWCOS.8xp

Prompt A,B,C
"//LAW OF COSINES: SIDES A,B AND INCLUDED ANGLE C IN DEGREES"
(C*π/180)→R
√(A²+B²-2*A*B*cos(R))→X
ClrHome
Disp "3RD SIDE:"
Disp X

The screenTry it yourself

Press run to power on the screen and step through the program.

Try 5, 7, 60 — the third side comes out to about 6.25.

Ideal gas law solver

ChemistryFree

What you’d ask“Build a solver for the ideal gas law that works no matter which variable I'm missing — pressure, volume, moles, or temperature.”

The codeIDEALGAS.8xp

Lbl 0
Menu("SOLVE FOR...","PRESSURE",1,"VOLUME",2,"MOLES",3,"TEMP(K)",4)
Lbl 1
"//IDEAL GAS LAW: PV=NRT, R=0.0821 L*ATM/(MOL*K)"
Prompt V,N,T
(N*0.0821*T/V)→P
ClrHome
Disp "P (ATM) ="
Disp P
Stop
Lbl 2
Prompt P,N,T
(N*0.0821*T/P)→V
ClrHome
Disp "V (L) ="
Disp V
Stop
Lbl 3
Prompt P,V,T
(P*V/(0.0821*T))→N
ClrHome
Disp "N (MOL) ="
Disp N
Stop
Lbl 4
Prompt P,V,N
(P*V/(0.0821*N))→T
ClrHome
Disp "T (K) ="
Disp T

The screenTry it yourself

Press run to power on the screen and step through the program.

Solve for pressure with V=10, N=1, T=300 — about 2.46 atm.

Projectile motion solver

PhysicsFree

What you’d ask“Projectile motion — given a launch speed and angle, find the time of flight, the max height, and the range.”

The codePROJMOTN.8xp

Prompt V,A
"//PROJECTILE MOTION: V=LAUNCH SPEED M/S, A=ANGLE DEG, G=9.8 M/S²"
(A*π/180)→R
(2*V*sin(R)/9.8)→T
((V*sin(R))²/19.6)→H
(V²*sin(2*R)/9.8)→X
ClrHome
Disp "TIME (S):"
Disp T
Disp "MAX HT (M):"
Disp H
Disp "RANGE (M):"
Disp X

The screenTry it yourself

Press run to power on the screen and step through the program.

Try 20 m/s at 30° — about 2.04s flight, 5.10m high, 35.35m range.

Reynolds number / flow regime

Fluid dynamicsFree

What you’d ask“A fluid dynamics program that computes the Reynolds number for pipe flow and tells me if it's laminar, transitional, or turbulent.”

The codeREYNOLDS.8xp

"//REYNOLDS NUMBER: RE=(DENSITY*VELOCITY*DIAMETER)/VISCOSITY"
Input "DENSITY?",D
Input "VELOC M/S?",V
Input "DIAM M?",L
Input "VISC PA*S?",U
(D*V*L/U)→R
ClrHome
Disp "RE ="
Disp R
If R<2300
Then
Disp "LAMINAR FLOW"
Else
If R>4000
Then
Disp "TURBULENT"
Else
Disp "TRANSITIONAL"
End
End

The screenTry it yourself

Press run to power on the screen and step through the program.

Try 1000, 2, 0.05, 0.001 (water) for turbulent, or 900, 0.1, 0.05, 0.01 (oil) for laminar.