Math Is Fun Forum

Dharshi

Member

Registered: 2006-10-31

Posts: 56

Help me with geometry

(1) Solve cos⁡2x= -1/2 for x. Give a general formula for all of the solutions. List six specific solutions.

(2) f(x)= (4x^2- x-3)/(2x^2- 11x+5)
a) Find all of the intercepts
b) Find all of the asymptotes.
c) Build a sign chart to define when the graph is above and below x axis.
d) Use this information to build a graph.

3)   Solve the exponential equation 7^2x+ 7^(x+1)- 120=0.

I tried all these problems, for pr (1) i got 5pi/6, for (2) got 2,6 for a and b
and for (3) i got the ans as 0.715

Is my ans correct? Am confused with them

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Help me with geometry

Hi;

For 3)

If that is your equation then the answer of x = .715 is not correct. You can verify that by plugging in. Have you copied the question correctly?

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,623

Re: Help me with geometry

hi Dharshi

I've been looking at back over your posts since March 2007.

This is your 30th post.

It would be most interesting to know what courses you are studying.  It would enable you to receive better help because we'd know the right level for replies.

Have you ever read this:

http://www.mathisfunforum.com/viewtopic.php?id=14654

This is not a free 'we'll do your homework for you site'

And how often in all those posts did you post back and thank the helper for spending time trying to help you or even showing that you have benefited from the effort they have made.  Well I can tell you, because I've just counted.  I make it 7 and once you helped someone else.  Thanks for that by the way. 

Mostly you post a lot of questions, without showing any evidence that you've actually tried them yourself.

As regards your latest efforts, all those answers are not just wrong, they bear little resemblance to the questions.

It looks like you just made them up so we'd think you had made an effort.

If they're represent your genuine effort then you need to show us what you did so we can get you on the right track.

I have done all your questions and I have saved my post ready for you.

Here's what you need to do to get it.

(i)  Show us how you got your answers.  Then we can help with where you are going wrong.

(ii) Tell us what you know already.  That makes it easier to target the help where it is needed.

(iii) Be prepared to respond when someone makes an effort for you.  It's nice to know one's efforts have been worth it.

I don't think that is much to ask in return for a lot of help with your maths.

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob