Find sine, cosine and tangent
Get sin, cos or tan of an angle, here sin 50, cos 50 and tan 50 in degrees.
For an angle in a right triangle, sine is opposite over hypotenuse, cosine is adjacent over hypotenuse, and tangent is opposite over adjacent.
The examples use 50 degrees. The answers are sin 50 = 0.7660444431, cos 50 = 0.6427876097 and tan 50 = 1.191753593.
Classic Graphing 84
Start on the main screen: Press 2nd then mode (QUIT) to get back to the home screen. Pressing clear on a menu also backs out of it.
Switch to degree mode first.
mode▼▼▶enter2ndQUITmodePress the trig key, type the angle, close the bracket and press enter. Do this for sin, cos and tan.
sin50)entercos50)entertan50)enter
You should see.7660444431 .6427876097 1.191753593
Classic Scientific 30
Start on the main screen: Press 2nd then mode (QUIT) to leave any menu or screen and return to the calculation screen.
This model starts in degrees. Press sin, type 50, close the bracket and press enter.
sin50)enter
You should see0.7660444431
Natural Scientific 991
Start on the main screen: Press MENU, then 1 (Calculate) to return to the main calculation screen. AC clears the line you are on.
This model starts in degrees. Press sin, type 50 and press =. The closing bracket is optional at the end.
sin50=Repeat with cos and tan.
cos50=tan50=
You should see1.191753593
Natural Color Graphing
Start on the main screen: Press MENU then 1 to open Run-Matrix, the main calculation screen. Press EXIT to back out of a bar or screen, and SHIFT then EXIT (QUIT) to return to the app start.
Switch the angle unit to degrees (SET UP).
SHIFTSET UPMENU▼▼F2EXITType the sin and cos calculations and press EXE after each one. Both answers stay on screen.
sin50EXEcos50EXE
You should see0.7660444431 0.6427876097
Classic CAS
Start on the main screen: Press home to open the Home menu (Calculator, Graphs, Settings, and more). Choose Calculator, or press esc to go back to the calculation page.
Switch to degrees in Settings.
menu9▼▶enterenterenterType sin(50). Hold ctrl and press enter to get a decimal. A plain enter keeps the exact form.
sin50)ctrl≈enter
You should see0.766044
RPN Scientific 15
Start on the main screen: There is no menu to leave. Press the back arrow to clear a number you are typing, or CLx (g then back arrow) to clear the X register.
This model starts in degrees. Key in 50, then press SIN.
50SINKey in 50 and press COS to put the cosine next to it.
50COS
You should see0.7660 0.6428
RPN Advanced 42
Start on the main screen: Press EXIT (once or twice) to close any menu and return to the plain stack view of Y and X.
Key in 50 and press SIN, then COS, then TAN on fresh numbers. The stack shows the latest results.
50SIN50COS50TAN
You should seey: 0.6428 x: 1.1918
RPN Power 48
Start on the main screen: Press ON to cancel what you are typing, then use the stack view. Open the MODE or VAR menu any time; the stack is always shown above the menu row.
This model starts in radians, so choose DEG on the MODE menu first.
MODEF5Key in 50 and press SIN.
50SIN
You should see.766044443119
Tips
- Always check the angle mode first. sin 50 in radian mode is a completely different number.
- Tangent of 90 degrees does not exist. Expect an error message there.
Related guides
- Set degrees or radiansTell the calculator whether angles are measured in degrees or radians before you use sin, cos or tan.
- Find an angle from a ratioUse the inverse trig functions (sin⁻¹, cos⁻¹, tan⁻¹) to turn a ratio back into an angle.
- Check unit circle valuesFind the exact values of sin, cos and tan at 30, 45 and 60 degrees.