Question

Can someone help me solve this calc problem? It's attached.

Answer 1

Sample problem:

Answer 2

you have the solution with the explanation, so what else do you need?

Answer 3

I have a sample problem. I've tried applying the steps to the actual problem but it's confusing.

Answer 4

So instead of substituting 6 and 1 into the v's, you'll substitute 5 and 2.

Answer 5

The substitution takes place at the part where the expression is in square brackets. [ ]

Answer 6

You'll plug in 5 first and evaluate. Keep that answer on the side somewhere.

Then you'll go back to the square brackets again, plug in 2 and evaluate. Whatever you get as the answer, you'll subtract that from the answer you got when you plugged in 5.

Answer 7

Can you wait while I do it, and tell me if it's correct?

Answer 8

Yes.

Answer 9

I got 77.5 when I plugged in 5.

Answer 10

I got -7.5

Answer 11

There's an extra negative sign next to the red negative sign. Ignore the extra one.

Answer 12

\[{-3(5)^{2}\over 2}+6(5)\]

Answer 13

Okay, so if I plug in 1, I'll get -3/2+8 = 6.5

Answer 14

No. 4.5.

Answer 15

Look at the equation I wrote above.

Answer 16

What do you get when you evaluate that expression?

Answer 17

Oh, I forgot to square it.

Answer 18

Then I get: (-7.5+4.5) - (-3/2 +8) = -9.5 or -19/2.

Answer 19

It's cool.

Answer 20

It's not correct though.

Answer 21

You're doing more than what it's asking for. The only values you're evaluating are 5 and 2. Not 6 and 1.

Answer 22

6 and 1 are solely used in the example.

Answer 23

You never answered my question. What do you get when you evaluate the expression I wrote above?

Answer 24

-7.5

Answer 25

Awesome. Now imagine the 5 is gone and a 2 is in its place in the expression above. What do you get now?

Answer 26

Replace BOTH 5s with 2s. Not just the one on the left.

Answer 27

6

Answer 28

Perfect. Now the last step is subtracting that 6 from -7.5:

-7.5 - 6 =

Answer 29

-13.5

Answer 30

Awesome : )

Answer 31

But if you look at the sample problem, they subtracted another part too.

Answer 32

They subtracted the value of the expression when a 1 was plugged in.

We subtracted the value of the expression when a 2 was plugged in.

Answer 33

I got -8 and it's still wrong.

Answer 34

-8 on which problem?

Answer 35

Ugh. It's + 8 not +6

Answer 36

\[{-3v ^{2} \over 2}+8v\]

Answer 37

Answer: -7.5 or -15/2

Answer 38

Okay

Answer 39

Sorry. I thought the expressions were the same in the example and actual problems.

Answer 40

It's okay. Can you help with another problem?

Answer 41

If you're not busy?

Answer 42

Sure.

Answer 43

Sample:

Answer 44

4/3

Answer 45

Start off exactly as the example starts by dividing u and -4 by the square root of u.

This gives you:
\[\int\limits_{1}^{9}u ^{1/2}-4u ^{-1/2}\]

Answer 46

Then integrate each term.

Answer 47

\[[{2 \over 3}u ^{3/2}-8u ^{1/2}]\]

Answer 48

Plug in 9 first, and evaluate.

Plug in 1 afterwards, then evaluate.

Subtract the second answer from the first one.

Answer 49

Take care and don't forget to mark a Best Response. Thank you