1. If
, then
. So
.
2. With
, we differentiate once with respect to
and get
![\dfrac{\mathrm d}{\mathrm dx}[x^2+y^2]=\dfrac{\mathrm d}{\mathrm dx}1](https://tex.z-dn.net/?f=%5Cdfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dx%7D%5Bx%5E2%2By%5E2%5D%3D%5Cdfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dx%7D1)


Differentiate again with respect to
and we get


(where
).
3. Check the one-side limits where the pieces are split. For
to be continuous everywhere, we need


In the first case, we have


and
, so it's continuous here.
In the second case, we have


so
is discontinuous at
.
4. If
, then
.
5. If
, then
. So
.
6. The average velocity over [1, 2] is given by

7. If
, then
. So
.
8. If
, then

Differentiating, we get

So
.
9. If
, then
. So 
10. If
, then
. So
.
Suppose Megan has enough money to buy 1 hat and 2 shirts for $21 and then another 2 hats and 1 shirt for $18. In total, she has bought 3 hats and 3 shirts for $39. But she has enough for only 1 hat and 1 shirt and so Megan has 39 ÷ 3 = $13.
1) Yes, there are many functions that have those x-intercepts with the same domain.
2) Yes, there are many functions with those x-intercpets, domain and range.
In fact, you might draw as many functions as you want that meet the specifications of both statements.
39. each term is ten more than the term before it :)