URGENT: Need some help with math problems, please.

[buddy]

I'm clepping out of precal on Monday but I'm not so sure if I'm going to pass this test :shrug: ...and I need help! :help: So if you know what's going on in the following problems, please solve and if you're really, bored, please explain! :0074 Thanks.

-Buddy's Daughter :mj01:


1) In the xy-plane, the graph of y=x^2+bx+c is symmetric about the line x=3 and passes through the point (5,2). What is the value of c?


2) (sin t + cos t)^2 = ?

3) .4=2^-x (logarithms)

 

[gardenweasel]

I'm clepping out of precal on Monday but I'm not so sure if I'm going to pass this test :shrug: ...and I need help! :help: So if you know what's going on in the following problems, please solve and if you're really, bored, please explain! :0074 Thanks.

-Buddy's Daughter :mj01:


1) In the xy-plane, the graph of y=x^2+bx+c is symmetric about the line x=3 and passes through the point (5,2). What is the value of c?


2) (sin t + cos t)^2 = ?

3) .4=2^-x (logarithms)

note to self:..."don`t play scrabble with buddy`s daughter"...

 

[Julene]

1. b = -6, c = 7

I don't know how to do 2 or 3.

 

[MadJack]

I'm clepping out of precal on Monday but I'm not so sure if I'm going to pass this test :shrug: ...and I need help! :help: So if you know what's going on in the following problems, please solve and if you're really, bored, please explain! :0074 Thanks.

-Buddy's Daughter :mj01:


1) In the xy-plane, the graph of y=x^2+bx+c is symmetric about the line x=3 and passes through the point (5,2). What is the value of c?


2) (sin t + cos t)^2 = ?

3) .4=2^-x (logarithms)

I'm going to change your thread title so you get the help you need.

:0008

 

[kosar]

Buddy,

Get agents email from Jack. He'll take care of this.

 

[buddy]

Julene Please Explain... I've looked all over youtube and it's just not happening.

 

[KotysDad]

Buddy,

Here is an explanation for (1).

If it's symmetric about the line x = 3, and it passes through (5,2) then it must also pass through (1,2).

So plug those into your equation and you get...

2 = 25 + 5b + c
2 = 1 + b + c

Subtract the second equation from the first and you get

24 = 4b which means b = -6

Plug that into either equation and you get c = 7.


For number 3, you need to take the log of both sides of the equation.

log (.4) = log (2^-x)

Using properties of logs, you get

log (.4) = -x log(2)

log (.4) / log (2) = -x then negate both sides.

-1.32 = -x so x = 1.32


Gimme some time for the trig identity.

 

[Nosigar]

3) is x= 1.322... i think

log2(.4) = - x

 

[MadJack]

Buddy,

Here is an explanation for (1).

If it's symmetric about the line x = 3, and it passes through (5,2) then it must also pass through (1,2).

So plug those into your equation and you get...

2 = 25 + 5b + c
2 = 1 + b + c

Subtract the second equation from the first and you get

24 = 4b which means b = -6

Plug that into either equation and you get c = 7.


For number 3, you need to take the log of both sides of the equation.

log (.4) = log (2^-x)

Using properties of logs, you get

log (.4) = -x log(2)

log (.4) / log (2) = -x then negate both sides.

-1.32 = -x so x = 1.32


Gimme some time for the trig identity.

:dizzy:

 

[KotysDad]

For (2), if you expand the function (think FOIL), you get

sin^2 t + cos^2 t + 2 sin t cos t

There is an identity that says sin^2 t + cos ^2 t = 1 so you can rewrite the new function as

1 + 2 sin t cos t.

Not sure you can reduce it from there.

 

[Sportsaholic]

:dizzy:

:shrug:

This site used to have so much promise :0corn

 

[MadJack]

I've never used one of these things

^
^^^^^^^^^^^

^^^^^^^^^^^^^^^^^^^^^^^

^^^^^^^^^^

:0008

 

[MadJack]

:shrug:

This site used to have so much promise :0corn

what you talking about? change the thread title and she gets her answer damn near right away.

thanks KD, you the man on this stuff. :0008

 

[ppabart]

Let me know when I need to grade everyones' papers

 

[Sportsaholic]

what you talking about? change the thread title and she gets her answer damn near right away.

thanks KD, you the man on this stuff. :0008

Talking about I don't understand a thng their talking about :0008 ^**6@^^!#**^

Usually takes me 8-10 beers to not understand things :facepalm:

 

[MadJack]

Talking about I don't understand a thng their talking about :0008 ^**6@^^!#**^

Usually takes me 8-10 beers to not understand things :facepalm:

marine says math is all common sense and we are all idiots :shrug:

simple math :0002

 

[The Judge]

marine says math is all common sense and we are all idiots :shrug:

Marine is right on both counts.

 

[buddy]

Thank You Everyone, Especially KotysDad!

Thank You Everyone, Especially KotysDad!

Thank You Everyone, Especially KotysDad! (again)

:0074

 

[kickserv]

 

[Nole]

I got 4 for questions 1, 2 and 3.


Ask whenever, I'm here to help.

Take care.


nole