Principal value of Arccos(-1)

You may have wondered what Euler's Identity means

I hate to break it to you but it just means

Equating respective real and imaginary parts,

which you probably already knew.

From the first part,

That's in the principal value range of cosine.

π

x=-2

infinite number of lines, so there is an infinite number of equations.

step-by-step explanation:

there are an infinite number of line that passes through the point (-2,5)

x=-2   is one line that passes through the point

y = 5 is another line that passes through the point

(these two lines are perpendicular to each other).

since the number of   numbers are infinite and the slope is the ratio of two numbers,(change in y over change in x) we can have an infinite number of slopes.     our only condition is that it passes through the point (-2,5)

step-by-step explanation:

what grade level is this? need to know so i can look in my old textbooks!