Can anyone help on this question

PSLE marks the graduation of Primary school students and their entry into Secondary schools as teenagers. Discuss all issues about Secondary schooling here.

Can anyone help on this question

Postby bluesky63 » Mon Feb 23, 2015 11:31 pm

Image Hi

Anyone can help in this question?

Thanks1

bluesky63
YellowBelt
YellowBelt
 
Posts: 18
Joined: Tue Jul 12, 2011 9:18 am
Total Likes: 0


Re: Can anyone help on this question

Postby bluesclue » Tue Feb 24, 2015 7:18 am

1. Find out the relationship of the figure. The distance between the boy and the heli is the hypotenuse. For right angled triangle, the 3 sides are related by sum of squares of the two short sides --> …….. theorem

2. Given one side is changing at 25m/s , make this side x, and rate of change of x, dx/dt =25 m/s

3. Given another side is constant, so the 3rd side is…. y= f(x)=theorem from step 1. find dy/dx

4. Using chain differentiation, rate of change of y, dy/dt= dy/dx. dx/dt

5. post back if you still need more clues.

bluesclue
OrangeBelt
OrangeBelt
 
Posts: 74
Joined: Tue Oct 21, 2008 2:25 pm
Total Likes: 0


Re: Can anyone help on this question

Postby bluesky63 » Tue Feb 24, 2015 12:49 pm

Hi,

Can explain more on how to form the y = f(x)? Thanks !

bluesky63
YellowBelt
YellowBelt
 
Posts: 18
Joined: Tue Jul 12, 2011 9:18 am
Total Likes: 0


Re: Can anyone help on this question

Postby bluesclue » Tue Feb 24, 2015 3:07 pm

Image

bluesclue
OrangeBelt
OrangeBelt
 
Posts: 74
Joined: Tue Oct 21, 2008 2:25 pm
Total Likes: 0


Re: Can anyone help on this question

Postby bluesky63 » Tue Feb 24, 2015 3:12 pm

Hi bluesclue,

what is the x value to sub in dy/dx ? thanks

bluesky63
YellowBelt
YellowBelt
 
Posts: 18
Joined: Tue Jul 12, 2011 9:18 am
Total Likes: 0



Re: Can anyone help on this question

Postby pinkapple » Thu Feb 26, 2015 4:13 pm

bluesky63 wrote:Hi bluesclue,

what is the x value to sub in dy/dx ? thanks

X is the horizontal distance so x = 72 add required by question

pinkapple
BlueBelt
BlueBelt
 
Posts: 345
Joined: Sun Nov 29, 2009 5:09 pm
Total Likes: 0


Re: Can anyone help on this question

Postby bluesky63 » Fri Feb 27, 2015 10:39 am

pinkapple wrote:
bluesky63 wrote:Hi bluesclue,

what is the x value to sub in dy/dx ? thanks

X is the horizontal distance so x = 72 add required by question


Thanks a lot... Got it !

bluesky63
YellowBelt
YellowBelt
 
Posts: 18
Joined: Tue Jul 12, 2011 9:18 am
Total Likes: 0



Return to Secondary Schools - Academic Support