Theta Calculator

The theta calculator takes output of the function, asin, acos and atan and returns arcsin, arccos and arctan. It is built for quick answers, for checking somebody else’s arithmetic, and for the moments when a formula book is not within reach.

What Is the Theta Calculator?

The theta calculator works through output of the function, asin, acos and atan to give you arcsin, arccos and arctan.

It is aimed at the case where you know the method but not the arithmetic: schoolwork, a quick check on a worked example, or a figure that needs to be right first time.

How the Theta Works

Each step is applied in order and depends only on the values before it, which makes it possible to follow the calculation rather than take it on trust.

If you are working through the same problem by hand afterwards, compare the intermediate values. That is where a mistake usually shows itself.

Checking Your Own Working

Round sensibly as you go and keep the full precision in the calculator. Rounding too early is the most common way of getting a right method to give a wrong answer.

Where a result should be a whole number, such as a count, check it against the constraint that produced it. A fraction of a person is a sign that something upstream needs revisiting.

A Worked Example

Working through an example, with output of the function set to 10, asin set to 5, acos set to 2, the calculator returns arcsin of -, and arccos of -, and arctan of 1.47. Substitute your own figures and the same steps produce the same kind of answer.

Frequently Asked Questions

What do I need to work out arcsin?

Enter output of the function, asin, acos and atan. The calculator then works through the relationship and reports arcsin, arccos and arctan.

What does the theta actually calculate?

It takes output of the function, asin, acos and atan and converts them into arcsin, arccos and arctan using the standard relationship for this problem. Each step is applied in turn, so every output is traceable back to the numbers you typed in.

How should I enter output of the function?

Use the value you actually have, in the unit shown next to the field. Enter every value in the same unit system. The calculator assumes the figures you supply are consistent, so it cannot correct a mistake that happens before the calculation starts.

Is the answer exact?

It is as exact as the formula and the inputs allow. The method itself is the standard one for this problem, so the only sources of error are the figures you enter and the precision you ask for.

Does anything you type get stored?

No. The whole calculation runs inside your browser, and nothing you enter is uploaded, logged or sent anywhere.

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