Warning: Illegal string offset 'html' in /home/hsn/public_html/forum/cache/skin_cache/cacheid_1/skin_topic.php on line 909

More Help - HSN forum

# More Help

4 replies to this topic

### #1Ron90

Showing Improvement

• Members
• 15 posts
• Gender:Not Telling

Posted 21 January 2008 - 07:37 PM

Yeah im again stuck at a question:

(b) Determine the exact value of the
x-coordinate of P, the point where
the graph intersects the x-axis

I have figured out the eq of function is: y = 2Sin(3x)-1 0<x<120

Any ideas? Thanks

### #2Marcus

Site Swot

• Members
• 147 posts
• Location:Aberdeen
• Interests:Guitar - Passed my grade 6 :D :D<br />Write computer programs - won Heriot-Watt programming challenge 2006 and 2007 :D<br />
• Gender:Male

Posted 21 January 2008 - 07:55 PM

Are you sure you have the correct equation there...I'm getting 2 answers
=-=-=Marcus=-=-=

### #3Ron90

Showing Improvement

• Members
• 15 posts
• Gender:Not Telling

Posted 21 January 2008 - 08:00 PM

QUOTE(Marcus @ Jan 21 2008, 07:55 PM)
Are you sure you have the correct equation there...I'm getting 2 answers

yea i got 2 too, but one is >120 so i crossed that one out.

But the one i had left was 10, and the answer is 50

### #4Marcus

Site Swot

• Members
• 147 posts
• Location:Aberdeen
• Interests:Guitar - Passed my grade 6 :D :D<br />Write computer programs - won Heriot-Watt programming challenge 2006 and 2007 :D<br />
• Gender:Male

Posted 21 January 2008 - 08:06 PM

hmmmm, I got both 50 and 10, is there something in the question that ruled out 10?, and I think you ruled out the one >120 too early, make sure you don't ignore answers that are out of range until the very end, they may end up coming back into range
=-=-=Marcus=-=-=

### #5Ron90

Showing Improvement

• Members
• 15 posts
• Gender:Not Telling

Posted 21 January 2008 - 08:32 PM

QUOTE(Marcus @ Jan 21 2008, 08:06 PM)
hmmmm, I got both 50 and 10, is there something in the question that ruled out 10?, and I think you ruled out the one >120 too early, make sure you don't ignore answers that are out of range until the very end, they may end up coming back into range

Ok what you have is right, the graph shows it hits 0 twice before 60 and so that P points to the second one so that makes sense. Thanks!

#### 1 user(s) are reading this topic

0 members, 1 guests, 0 anonymous users