Degrees intead of radians - Texas Instruments TI-81 Calculator

1 degrees = 0.0174532925 radians
1 radian = 57.2957795 degrees

When the angle unit is in radians
sin^-1(0.184)=0.1850543940 radians
When angle unit is in degrees
sin^-1(0.185)=10.60283581
Your calculator is calculating the functions correctly)
In the following screen captures the sine of the values is calculated with the unit specified inside the formula (degree symbol and radian symbol are inserted to show you the unit). In the last calculation the value of the sine is practically 0.184
Remember that when angle is in radians, for very small angles (less than 10 degrees), sin(x) and tan (x) are about equal to the value of the angle in radians

TWO THINGS YOU NEED TO KNOW, Eli.1. Secant will NEVER return a degree measure (or even a radian measure) no matter what computer or calculator you use. The reason is because secant returns the ratio of sides (hypotenuse over adjacent), which has a range of and find its reciprocal (ie, flip the number upside down: the reciprocal of 5 is one-fifth). That's all.B. TI-84 only uses the three basic trig functions. Secant is the reciprocal of cosine. Therefore, in order to find the secant of -1.2 radians you need to be in Radian mode (see #2 above). From there, you just find the cosine of -1.2 and take that values reciprocal (ie, flip the number upside down: the reciprocal of 10 is point one) . That's all. Math lesson: 1 Radian = 180 Degrees. Therefore, 1.2 Radians is roughly one-third of pi, therefore it is roughly one-third of 180 degrees; therefore -1.2 radians would be nearly -60 degrees (a very friendly angle measure). I hope that helps If not, you should call Texas Instruments because they've got friendly people who are happy to assist anyone. Questions like this are right up their ally, advanced questions like the syntax of the poisson cumulative distribution function are not. So, you're fine. For in depth math help holler at www.THEMATHCHEETAH.comIn Short: Secant returns ratios and NOT degrees or radians. Secant is the reciprocal to cosine. Arcsecant WILL return degrees/radians. Your calculator can be set to either mode.TEXAS INSTRUMENTS >>>>> all calculators ever made.

Press "Mode" Check to see if you are in radian mode or degree mode (one of the top categories)
If you are entering your numbers from sin, cos, and tan as degrees and you are in radians, your answers will be off. Same goes for if you are inputting radians while in degree mode. Hope this helps

Most likely you do have the calculator in radians (or if you are working in radians, you have it in degrees). Press the mode button, move cruser down to "radians degrees" highlight degrees. and press "2nd quit". things sould be better!

Press the [MODE] key to access the mode comfiguration screen .
Set angle unit to to radian (see above)
Enter angle value in Decimal degrees only, use the [2nd][ANGLE] key sequence to have access to the degree symbol. The degree symbol must imperatively appear at the end of the angle value.



Here are some examples
If you use angle values in DMS, it will not be converted to radians, but to decimal degrees.
If you omit the degree symbol there is no conversion.



A general formula is Pi radians =180 degrees

Hello,
With the TI8x/TI8xPlus you can enter an angle in degrees (Angle mode must be set to degrees) and convert it into DMS representation the following way. Exemple
18.675 [2nd][ANGLE][4] [ENTER] gives 18deg 40' 30''
If Angle [MODE] is set to degrees you can enter a number in radians and convert it into degrees. Exemple How many degrees are ther in 1rad ?
[1][2nd][ANGLE][3] display 1 with a small r as superscrit. Pressing [ENTER] yields 57.29577951

To convert 1rad into DMS, takes a little effort but can be done: you have
to convert radians to degrees and the result [ANS] into DMS.

You cannot use an angle written in DMS in any calculation.
But if you want to convert an angle from degrees to radians enter your number and divide by 57.29577951

Hope it helps

Alot of people seem to be having this problem. Angles can be measured in two units, degrees and radians. Your calculator is currently doing everything in terms of radians. I have an 84 but I'm sure the 83 is similar, go under MODE and look for Degrees and Radians and make sure you choose degrees. if you have to convert, 360[degrees] = 2* pi [radians]
(easy to remember, 360deg in a circle, 2pi radians in a circle)
Good luck

Alot of people seem to be having this problem. Angles can be measured in two units, degrees and radians. Your calculator is currently doing everything in terms of radians. I have an 84 but I'm sure the 83 is similar, go under MODE and look for Degrees and Radians and make sure you choose degrees. if you have to convert 360[degrees] = 2* pi [radians]
(easy to remember, 360deg in a circle, 2pi radians in a circle)
Good luck

reset ur calculator. press 2nd 6 F1 3 Enter. Note that all your data will be gone