Homework Help

Points A,B and C are taken in the ascending order lie on a straight line inclined at an...

user profile pic

roshan-rox | Valedictorian

Posted July 5, 2013 at 5:59 PM via web

dislike 1 like

Points A,B and C are taken in the ascending order lie on a straight line inclined at an angle `theta`  to the horizontal. AB = x and D is the point vertically above at height h from point C. CD subtends angles `alpha`  and `beta`  at A and B respectively.

 Show that

`d = (xsin(alpha+theta)sinbeta)/(sin(beta-alpha))` 

where d is the height of D above level of A.

1 Answer | Add Yours

user profile pic

jeew-m | College Teacher | (Level 1) Educator Emeritus

Posted July 5, 2013 at 7:39 PM (Answer #1)

dislike 1 like

The notation for this question is same as the following question.

http://www.enotes.com/homework-help/points-b-c-taken-ascending-order-lie-straight-line-442230#answer-624263

 

According to the new data d = DE

 

By the image we can say that;

`DE = d = ADsin(alpha+theta)`

 

In the previous question we have obtained that;

`AD = (xsinbeta)/(sin(beta-alpha))`

 

`d = (xsinbeta)/(sin(beta-alpha))xxsin(alpha+theta)`

`d = (xsinbetaxxsin(alpha+theta))/(sin(beta-alpha))`

 

So the required answer is proved.

`d = (xsinbetaxxsin(alpha+theta))/(sin(beta-alpha))`

 

Images:
This image has been Flagged as inappropriate Click to unflag
Image (1 of 1)

Sources:

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes