Click to Chat

1800-2000-838

+91-120-4616500

CART 0

• 0

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
```        If the line segment joining the points P(x1,y1) and Q(x2,y2) subtends an qngle @ at origin O
prove that OP.OQcos@ = x1x2 +y1y2```
6 years ago

Fawz Naim
37 Points
```
```
6 years ago
Devasish Bindani
45 Points
```										hey yar
op.oqcos@=>x1.x2cos0+x1.y1cos90+x2.y1cos90+x1.y2cos90+x2.y2cos90+y1.y2cos0
since (x1 and x2) and (y1 and y2)are in straight line

```
6 years ago
Devasish Bindani
45 Points
```										hey yar
by resolution of vectors
op.oqcos@=>x1.x2cos0+x1.y1cos90+x2.y1cos90+x1.y2cos90+x2.y2cos90+y1.y2cos0
since (x1 and x2) and (y1 and y2)are in straight line

OP.OQcos@=x1x2+y1y2
since cos0=1 and cos 90=0
thus prooved
```
6 years ago
satyajit nandy
20 Points
```										 As the line OP and OQ subtends an angle @, so we can use cosine law...........
2.OP.OQ.cos@ =(X1^2+Y1^2)+(X2^2+Y2^2)- {(X1-X2)^2+(Y1-Y2)^}
=2X1X2+2Y1Y2
SO OP.OQ.COS@= X1X2 + Y1Y2
```
6 years ago
Think You Can Provide A Better Answer ?

## Other Related Questions on Analytical Geometry

View all Questions »
• Complete JEE Main/Advanced Course and Test Series
• OFFERED PRICE: Rs. 15,900
• View Details