Question about HP 15C Scientific Calculator

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Sinus calculation HP-15C

Try to fix a formula calculation on my HP-15C, which is in the book mention like this: sin 55 x Cos 45 x 1 x1 x 1 = 0.5792 how do i have to enter the values into calculater, enable to reach this result. Have try many different ways but just dont get it. Help highly appreciated

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  • HP Master
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Press g [DEG] 5 5 SIN 4 5 COS * 1 * 1 * 1 *

I don't know why you need the three multiplies by 1. This could be done as 5 5 SIN 4 5 COS *

Posted on Sep 03, 2013


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Posted on Jan 02, 2017

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SOURCE: conection with PC? -cant turn on calculator in server mode

You should get a USB cable.

If you do not want to, get a Secure Digital card (formatted in FAT). Turn calculator ON, Insert card in slot.
Then [LeftShift][FILES] Open the directory where files are. Select them and use the [Copy] soft key to copy files. Got to directory where you want them copied and Copy rhem there. Exit File Manager. Remove Card and insert in SD card slot in computer, etc.

If you install the latest ROM 2.15 ( the USB transfer option in IO parameters will show.

Hope it helps

Posted on Sep 10, 2009

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SOURCE: HP 15C calculator display showed

When you get the error press any key to suppress the error message. Put the calculator into PROGRAM mode and you will see the line where the error occurred.

Here is what the manual says for ERROR 4 (free translation)
The line number called is not used or does not exist (larger than 448); attempt to load a program line (instruction) where there is not enough space; line label inexistant.
My hunch is that you are attempting to divide by 0: The quantity of which you are taking the reciprocal (inverse function has another meaning) may have a 0 value.
Do not forget to check the input values.
Hope that will help you debug your program

Posted on Oct 14, 2009

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SOURCE: My HP 15C calculator recently developed a problem

If the keyboard test fails the calculator should be sent for repairs. One shop in Pennsylvania repairs most models, except the newer ones. The URL is Best of luck!

Posted on Jan 30, 2010

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SOURCE: The keys stick on my HP 12C calculator so that

Try glass cleaner with a paper towel. If that doesn't work you'll have to take it apart and remove the button pad.

Posted on Apr 22, 2010

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SOURCE: How do you enter an angle in degrees, minutes and seconds on the HP 33s ?

Enter than angle as 32.2010 then press left-shift [->HR] to convert to decimal degrees.

The ->HR function (and the companion ->H.MS are for working in hours-minutes-seconds, but they work just as well for degrees-minutes-seconds.

Posted on Nov 04, 2010

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1 Answer

How do you calculate sec174?

SEC, CSC & COT are the INVERSE of COS, SIN & TAN and are usually require hitting the "2nd F" or "Func" key of the calc to make:

SIN button work as COSEC,

COS button work as SEC

TAN button work as COT

Formulas are below:

sec x = 1
cos x

cosec x = 1
sin x

cot x = 1 = cos x
tan x sin x

Good luck!

Feb 05, 2013 | Sharp EL531 Scientific Calculator

1 Answer

Cot(x) = -0.6

Let's start with a little background.

The cot(x) is also known as the cotangent(x) and it equals 1/tan(x) which equals cos(x)/sin(x). I'm showing these formulas because your calculator may not have a cot button but it will probably have buttons for tan, cos, and sin.

Your calculator may also have buttons for tan-1, cos-1 and sin-1. These are the inverse functions for tan, cos, and sin. If you enter a number and then push the tan-1 button, the result is the angle whose tangent is the entered number. For example, it you enter 1 and push the tan-1 button the answer will be 45 deg because tan (45 deg) = 1.

Now let's look at the problem, cot(x) = -0.6.
The first thing we need to know is do you want the answer in degrees or radians? Your calculator will have both modes. The default mode when you first turn it on is probably degrees. If this problem is in radians you will need to change the mode of your calculator over to radians before we start.

If cot(x) = -0.6, then tan(x) = 1/-0.6 from the formula I showed in the background section.

This means tan(x) = -1.6666666...

Now we just enter -1.66666667 and hit the tan-1 button to get the answer.

If we're operating in radians the answer is -1.0307 radians.
If we're operating in degrees the answer is -59.036 deg.

I hope this helps you out.

Dec 06, 2011 | SoftMath Algebrator - Algebra Homework...

1 Answer

I dont know how to enter in a degree and get its COS, TAN, SIN ect.. Can anyone help me out with this.

Press the SIN, COS, or TAN key, type in the angle, and press ENTER. For example, to calculate the sine of 45 degrees, press SIN 4 5 ENTER

Make sure you have the angular mode set to degrees. It's the third line on the mode screen, which you get by pressing the MODE key.

Jan 30, 2011 | Texas Instruments TI-84 Plus Silver...

1 Answer

How to use calculator on how to evaluate trigonometric functions

The FX-115ES is somewhat different to other calculators you might know. The sequence of keys is more like writing up a calculation in a textbook, whereas for "normal" calculators operations are reversed in some places.
For example, with most calculators you would type 30 [sin] to calculate the sine function of 30 degrees, with the 115ES its [sin] 30 [=].

The 115ES has all the standard trigonometric functions:
  • Standard functions (sin, cos, tan), type the [sin], [cos] or [tan] key followed by the argument.
  • Inverse trigonometric (sin?¹, cos?¹, tan?¹), type [SHIFT][sin], [SHIFT][cos] or [SHIFT][tan] followed by the argument.
  • Hyperbolic functions (sinh, cosh, tanh), type [HYP][sin], [HYP][cos], or [HYP][tan] followed by the argument.
  • and finally inverse hyperbolic (sinh?¹, cosh?¹, tanh?¹), its [SHIFT][HYP][sin], [SHIFT][HYP][cos], or [SHIFT][HYP][tan] followed by the argument.
Arguments can be given as numbers with mantissa (2.718), as fractions (use the fraction key below [CALC]) or as degree, minute, second (30°12'45") using the [°'"] key for input. To switch between degrees (1 circle = 360°), radians (1 circle = 2?), or grad (1 circle = 400 gon), use [SHIFT][DRG>].

Jan 06, 2011 | Casio FX-115ES Scientific Calculator

3 Answers

TI89 is giving wrong answer for the integral of sec(x). Please help. It gives the answer as: ln[ |cos(x) / (sin(x)-1)| ] when it should be ln[ |(sin(x)-1) / cos(x)| ]. Why is it giving the wrong...

Hi danagasta,

If my last instructions did not work then you need to reset your RAM. You are missing the negative sign and, I have no idea where you got the absolute value inside the brackets.
Yes, the absolute value are used in books and, on integral tables but, I can asure you that the Ti 89 should not have produce them in this answer.

I'll stand behind that In( -cos(x) / (sin(x)-1)) is the correct answer. You can go ahead and simplify after the calculation to get the answer you want but, that is the good answer that Ti 89 is going to give you for the integral of sec(x).

Errors that do not match the suspected, I am pretty sure that Texas Instruments would have you clear the RAM. I do not like resetting the RAM but, I could not find the cause to why you got the answer you did. And so far no other expert has produced a solution to convince me otherwise.

I was not able to come up with any of the 3 answers MiB8888 did on my Ti 89. I am not saying that they are not good answers, they are book and integral tables answers. You are not going to get them on the Ti 89.

Jan 04, 2011 | Texas Instruments TI-89 Calculator

1 Answer

Differentiate each of the following w.r.t.x; 29.sin2xsinx

Use the rule for differentiating products of functions: ()' signifies derivative
(29*sin(2X)*sin(X))'= (29)'*sin(2X)*sin(X) +29* (sin(2X))'*sin(X) +29*sin(2X)*(sin(X))'
  1. (29)'=0 derivative of a constant is zero
  2. (sin(2X))'=cos(2X)*(2X)'=2*cos(2X)
  3. (sin(X))'=cos(X)
Result is
(29*sin(2X)*sin(X))'= 29*2*cos(2X)*sin(X)+29*sin(2X)*cos(X)

You could also have cast your formula in the form
sin(2X)*sin(X)= 1/2[ cos(2X-X)-cos(2X+X)]=1/2[cos(X)-cos(3X)]
then calculated the derivative of
which is
29/2*[-si(X) +3*sin(3X)]

The challenge for you is to prove that the two forms are equivalent
29*2*cos(2X)*sin(X)+29*sin(2X)*cos(X)=29/2*[-si(X) +3*sin(3X)]

Jun 21, 2010 | Vivendi Excel@ Mathematics Study Skills...

1 Answer

How to use the cosine,tangent etc functions of calculator fx-82ES plus

1.Set the correct angle unit required by your problem: degrees, radians, or grads. [SHIFT][MODE] [3:deg] or [4:Rad]

2. Press the key for the function COS, SIN, or TAN
[COS] displays Cos(

3.Enter the angle 12 deg Screen shows cos(12
Close the right parenthesis ) Screen shows cos(12)
4.Press [=] Screen displays 0.9781

If you want the inverse trigonometric functions you access them with arccos [SHIFT] [COS] (cos^-1)
arcsin [SHIFT][SIN] (sin^-1)
actan [SHIFT][TAN] (tan^-1)

You have to know the principal domain for the inverse trigonometric functions (see any book on trigonometry) to understand the results.
Hope it helps.

Nov 05, 2009 | Casio Office Equipment & Supplies

4 Answers

Trig Identities

Change csc to 1/sin. Find a common denominator and add the two left terms.
1/sin - sin = (1 -sin^2)/sin. Rewrite formula
(1 - sin^2)/sin = cos^2/sin Divide out the /sin.
1 - sin^2 = cos^2 Rearange.
1 = cos^2 + sin^2 Yes, that's true. It's like the Pythagorean formula.

May 22, 2008 | Super Tutor Trigonometry (ESDTRIG) for PC

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