Question

1-2cosa​

Answer 1

Ответ: я не знаю ответа, но могу посоветовать приложение " Mathway "

Объяснение:

Answer 2

The expression $1-2\cos(a)$ represents a mathematical formula involving the cosine function. Here's a brief explanation of its meaning:

$\cos(a)$ is the cosine of angle $a$. It is a trigonometric function that gives the ratio of the length of the adjacent side to the hypotenuse in a right triangle with angle $a$.

So, $1-2\cos(a)$ means you take the cosine of angle $a$, multiply it by 2, and then subtract that result from 1.

Depending on the value of angle $a$, the expression will yield different numerical results between -3 and 1. The cosine function oscillates between -1 and 1, so the term $2\cos(a)$ will oscillate between -2 and 2. Subtracting this term from 1 will then give values between -3 and -1 when $\cos(a)$ is positive and between -1 and 1 when $\cos(a)$ is negative.

If you have a specific value of $a$, you can calculate the exact numerical result by plugging it into the expression. For example, if $a = \frac{\pi}{3} \approx 1.047$, then $1-2\cos(a) = 1 - 2\cos\left(\frac{\pi}{3}\right) = 1 - 2\left(\frac{1}{2}\right) = 1 - 1 = 0$.