# # For Students

## # Getting Started

The video below covers getting started, including signing up for COSma Learning, enrolling in a new course, and what the main pages of the system look like. Visit this link to sign up for an account.

## # Completing Assignments

The video below covers how you might go about interacting with the assignments within the IMathAS system.

The video below covers entering answers into the COSma system.

## # Typing Math

The video below covers some of the basics of typing mathematical expressions into the IMathAS system.

The way you type math into your graphing calculator is very similar to how you should type it into iMathAS. Here is a table showing how to enter various mathematical expressions/operators.

EntryMeaningExample
+,-,*,/Add, subtract, multiply, divide"5+2*3-10" gives $5+2\cdot 3-10$ and "3/5" gives $\frac{3}{5}$
^Power or exponent"2^3" gives $2^3$
( )Parentheses for grouping"1/2*pi" gives $\frac{1}{2}\cdot\pi$ while "1/(2*pi)" gives $\frac{1}{2\pi}$
e, piStandard constants $e$ and $\pi$"2 pi r" gives $2\pi r$ and "e^3" gives $e^3$
x, y, t, etc.Variable names"3*x^2" gives $3\cdot x^2$
_Subscript, for variable and function names"t_1" gives $t_1$ and "log_b(y)" gives $\log_b(y)$
absAbsolute Value"abs(-4)" gives $\lvert-4\rvert$
sin, cos, tan, sec, csc, cot, sinh, coshStandard trig. functions"sin(2)" gives $\sin(2)$
arcsin, arccos, arctanInverse trig. functions"arccos(0.5)" gives $\arccos(0.5)$
sin^-1, cos^-1, tan^-1Inverse trig. functions"sin^-1(0.5)" gives $\sin^{-1}(0.5)$
log_bLog with base $b$"log_2(4)" gives $\log_2(4)$
ln, logNatural (base $e$) and common (base 10) log"ln(3)" gives $\ln(3)$
!Factorial"4! = 24" gives $4! = 24$
ooInfinity. Two lower case O's like the middle of the word "book""(-oo, oo)" gives $(-\infty, \infty)$

## # Why is that Wrong?

By default, for numerical questions, IMathAS checks to see if your answer is within 0.1% of the exact answer - if it is, you're answer is considered "correct." THIS IS VERY IMPORTANT If you round too early, your answer might not be within 0.1% of the exact answer and therefore IMathAS might tell you your answer in incorrect even if your thinking is correct.

To avoid this, round out to 5 or 6 decimal places if you must round. The better option is to enter a numerical expression and let IMathAS do the computation. Consider the following example.

Suppose the answer to a question is $\frac{1}{3}$. If you enter this into your calculator you might be tempted to round to 0.33. But 0.33 is actually 1% away from $\frac{1}{3}$ so your answer will be counted incorrect! Instead, enter 0.333333. Or even better! Enter "1/3" and IMathAS will do the computation for you.

When possible, enter expressions into IMathAS and let IMathAS do the computing for you. After all, this is what computers are for.