This problem demonstrates how you enter function answers into WeBWorK.

First enter the absolute value of -7 in the box below.

When entering the answer, you should just enter the value 7. But WeBWorK will also accept abs -7 or even abs-7.

Warning: WeBWorK will accept this or any other value equal to abs(-7), e.g. 7, or 14/2, or sqrt(49). However your instructor is almost certain to notice one of those incorrect ways of getting to a correct answer on a written assignment!

It is better to enter abs(x), even though WeBWorK will also accept abs x or even absx, because you are less likely to make a mistake. Try entering abs(2x) without the parentheses and you may be surprised at what you get. Use the Preview button to see what you get.

WeBWorK will evaluate standard calculations (such as abs or sqrt) before doing anything else, so abs 2x means first find the absolute value of 2 which gives abs(2) and then multiply by x.

Try it.

Now enter the calculation $2\sqrt{ t}$ using 2sqrt(t).

Note this uses the variable $t$ and not $x$. Try entering 2sqrt(x) and see what happens. Be carful to read the error statements in WeBWorK. They are trying to tell you where you made an error.

When WeBWork says an answer doesn't $parse$ correctly, that is it's overly computerish way of saying the answer doesn't fit the problem. It will also try to warn you that a parenthesis or some other closing symbol is missing.

Here's a tip from the lazy side! If you can highlight a text in a WeBWorK page, you can drag and drop it or copy into the answer box! Try it out. Enter 2sqrt(t) in the box above by highlighting, dragging and dropping. Be careful about picking up extra characters. But if you picked up an improperly placed period or comma, WeBWork will show you the error when you submit your answer. Drag/drop and copy make it much easier to do substitutions in formulas.

Your overall score for this problem is