MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
Menu
sneha sunil raikar Grade: 12
        

ABCDE is a pentagon. prove that  AB+AE+BC+DC+ED=2AC

8 years ago

Answers : (1)

AskiitianExpert Shine
10 Points
										

Hi


 Triangle law of vector addition

If two vectors are represented by two sides of a triangle in sequence, then third closing side of the triangle, in the opposite direction of the sequence, represents the sum (or resultant) of the two vectors in both magnitude and direction.


 


Here, the term “sequence” means that the vectors are placed such that tail of a vector begins at the arrow head of the vector placed before it.


 















Figure 3:
Triangle law of vector addition
 Triangle law of vector addition  (va1.gif)


 


The triangle law does not restrict where to start i.e. with which vector to start. Also, it does not put conditions with regard to any specific direction for the sequence of vectors, like clockwise or anti-clockwise, to be maintained. In figure (i), the law is applied starting with vector,b; whereas the law is applied starting with vector, a, in figure (ii). In either case, the resultant vector, c, is same in magnitude and direction.


Now divide the given pentagon in three parts by joining AB and AD. Consider triangle ABC , by triangle law, AB + BC = AC (1)


for triangle ACD , AC + CD = AD (2)


For triangle ADE , AD + DE = AE  (3)


From 2 and 3 we get  AC + CD = AE - DE .=> AC= AE + ED + DC (4)


Add (1) and (4) to get the desired answer.


 

8 years ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies
  • Complete JEE Main/Advanced Course and Test Series
  • OFFERED PRICE: Rs. 15,900
  • View Details
Get extra Rs. 3,180 off
USE CODE: CHEM20
  • Statistics and Probability
  • OFFERED PRICE: Rs. 636
  • View Details
Get extra Rs. 127 off
USE CODE: CHEM20

Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!! Click Here for details