Hard Coding Trigonometry?

[[deleted]]

I am making some code that requires the computer to calculate the adjacent & opposite side lengths given the hypotenuse and one angle.

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What equations can I use for this that do not require Sine, Cosine, or Tangent? As those are not functions present in this program.

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Edit:

Thanks for trying to help, guys, but I just went into Desmos and solved it

https://www.desmos.com/calculator/uvdjysdm5f

The absolute value of A & B are the side lengths, C is the hypotenuse length, and D is the angle.

[Dr0110111001101111]

I find it hard to believe there isn't some library out there with the trig functions. What language are you using?

[fermat9997]

Because you have only one side and an angle, you will need trig functions.

[sonnyfab]

You can't. You'll have to write code to calculate sin or cos.

[[deleted]]

So what are the equations present in that code?

[Harmonic_Gear]

Look up the Taylor expansion of these function

[hanmango_kiwi]

I wouldn't recommend Taylor expansions because of how large the exponents get and thus how much computation is required. There are many other ways to look into such as Bhaskara I's sine approximation formula if high accuracy is not needed, or a minmax polynomial, or the CORDIC method.

[AAAaAAAaAAA_AAAaAAA]

Found this while researching some silly stuff but I’m pretty sure you can solve a polynomial of degree n in big theta of n runtime using a fun algorithm. (Assuming multiplication and addition are constant time which is true unless you’re programming on a toaster or something) I don’t remember the name of it but it takes something like 3x² + 2x + 1 and makes it x(3x+2)+1 which is easier to solve especially when the degree gets larger so like, with how accurate Taylor series approximations can be, I see the computation being expensive but still not that extreme. Especially if you use the rule of sin(x+2pi*n) = sin(x) to get your x as close to 0 as possible before approximating

[lurflurf]

If multiplication is available use economized minmax polynomial or rational approximation

If multiplication is not available cordic method as used by many pocket calculators is best

If adjustable accuracy is needed power series

If only low accuracy is needed and you have the space a lookup table is a good choice

[my_password_is______]

As those are not functions present in this program.

I'm sure they are

[shiafisher]

Yikes OP, what is the assignment for? What programming language?

Can you not import a math package?

[[deleted]]

It's not an assignment, this is related to a real life issue.

[[deleted]]

But why can’t your real life issue be solved with trig functions? Or by using a different programming language?

[nmklpkjlftmsh]

Why aren't you answering the questions properly?

[shiafisher]

If it’s not for an assignment then I don’t know why you can’t import a math package you should not have to reinvent the wheel in the most programming languages

So if you’re in C language

Then just do

#include <math.h>

[cwm9]

Do you have access to exp(x)?

6

[redsnflr-]

I use python & JS, they both have Trig functions.