Question

Can you tell me why I got these 3 problems wrong for a medal?

Answer 1

Here's a graphing calculator if anyone needs it:
https://www.desmos.com/calculator

Answer 2

For the first one, when you plug in 3 into the equation, it equals 8, which is not <8.

Answer 3

Do you see it?

Answer 4

Also, for the second one, what happens when you take the absolute value of any number?

Answer 5

It is positive correct?

Answer 6

Correct! Now, knowing that whatever is in there, the outcome will ALWAYS be positive, meaning it can't be?..

Answer 7

and yes I do see what I did wrong on the first one. It was a simple addition error on my part.

Answer 8

one moment

Answer 9

No prob bob, take your time.

Answer 10

b cannot be less than zero, so C?

Answer 11

Correct!

Answer 12

For the last one, let me type out the algebraic process

Answer 13

y < x^3 -4x^2 +2
0 < (1)^3 -4(1)^2 +2
0 < 1 -4^2 +2
0 < 1 +16 +2
0 < 19
which is true, or did I do something wrong again?

Answer 14

Yes, you see, the power is not attached to the "4", its attached to the "1".

Answer 15

Ah. I see now.

Answer 16

The power is attached to the "x" in "4x"

Answer 17

So, when you work it out, eventually you get 0<-1 , which is false.

Answer 18

Oh okay. I understand now. Thank you so much for your help! :D

Answer 19

No prob bob. If you need any more assistance, feel free to ask.

Answer 20

Will do. :)