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## trigonometry – how do you type sec^2(0) on a calculator?

Here is again one of the times to remind everyone of the unfortunate way in which mathematics, and in particular trigonometric functions, are written in today’s systems.

$$\cos^{n}(x) = \begin{cases} [\cos(x)]^n & n\neq -1 \ \arccos(x) & n=-1\end{cases}$$

That is to say, on calculators, and many papers, if you see $\cos^{-1}(x)$ they do not mean the multiplicative inverse, $\sec(x)=\frac{1}{\cos(x)}$, but instead they mean to say the inverse function such that $\cos^{-1}(\cos(x)) = x$.

To avoid ambiguity, it is highly recommended to never write $\cos^{-1}$ and instead either write $\sec, \frac{1}{\cos}$ or $\arccos$ depending on what you intend to use.

(the other trigonometric functions suffer the same unfortunate ambiguity)

To calculate $\sec^2{x}$ on a graphing calculator, you should have the ability to write strings of functions with parenthesis and the like and can write it as:

$1 / (\cos(x))^2$$

If you are using a scientific calculator, then you could push the buttons in the following order: inputnumber for $x$,$~~~~\cos,~~~~x^2,~~~~x^{-1}$

(depending on the model of the calculator either inputnumber$~~~~\cos$ will give the value for cos(input) or you will need to reverse the order of the button presses to $\cos~~~~~$inputnumber.)

Evaluate sec(0)^2 | Mathway – Free math problem solver answers your algebra, geometry, trigonometry, calculus, and statistics homework questions with step-by-step explanations, just like a math tutor.44 PENS-ITS Metode Numerik Contoh • x – e-x = 0 x0 =0, e = 0.00001 45 PENS-ITS Metode Numerik Contoh • x + e-x cos x -2 = 0 x0=1 • f(x) = x + e-x cos x – 2 • f'(x) = 1 – e-x cos x – e-x sin x 46 PENS-ITS Metode Numerik 47 PENS-ITS Metode Numerik Permasalahan pada pemakaian metode newton raphson • Metode ini tidak dapat digunakanA secant of a circle is a line connecting two points on the circle. A tangent to a circle is a line that intersects a circle exactly once. When a nonparallel tangent and secant are given, their intersection point satisfies several interesting properties. These properties are very important when dealing with tangents in general, as they are almost always coupled with other secants, allowing

(PDF) Metode Numerik PENS-ITS Bab 2. Penyelesaian – Formula $\sec^2{\theta} \,=\, 1+\tan^2{\theta}$ The square of secant function equals to the addition of one and square of tan function is called the secant squared formula.Solution for sec^2(0)= equation: Simplifying sec 2 (0) = 0 Reorder the terms for easier multiplication: 0c 2 es = 0 Anything times zero is zero. 0c 2 es = 0 Solving 0 = 0 Couldn't find a variable to solve for. This equation is an identity, all real numbers are solutions.Compute answers using Wolfram's breakthrough technology & knowledgebase, relied on by millions of students & professionals. For math, science, nutrition, history

Tangent-Secant | Brilliant Math & Science Wiki – The secant is the reciprocal of the cosine. The cosine of 0 is well-defined, and is 1. Therefore, the secant of 0 is also 1. And the square of the secant of 0 is 1² = 1.Purplemath. In mathematics, an "identity" is an equation which is always true. These can be "trivially" true, like "x = x" or usefully true, such as the Pythagorean Theorem's "a 2 + b 2 = c 2" for right triangles.There are loads of trigonometric identities, but the following are the ones you're most likely to see and use.The derivative of arcsec 2 is particularly useful to calculate the inverse secant 2 as an integral. The formula for x is (arcsec x)' = $\frac{1}{|x|\sqrt{x^{2}-1}}$, |x| > 1, so for x = 2 the derivative equals 0.2886751346. Using the arcsec 2 derivative, we can calculate the angle as a definite integral: