If cos x. cosy+sinx.siny=-1 then cosx+co...

If `cos x. cosy+sinx.siny=-1` then `cosx+cosy` is :

A

`-2`

B

1

C

0

D

2

Text Solution

Verified by Experts

Topper's Solved these Questions

MIXTURE AND ALLIGATION
ADVANCED MATHS BY ABHINAY MATHS ENGLISH|Exercise QUESTIONS|101 Videos
MOCK TEST II
ADVANCED MATHS BY ABHINAY MATHS ENGLISH|Exercise MCQ|100 Videos

Similar Questions

Explore conceptually related problems

If cosx.cosy + sinx.siny = -1 then cosx + cosy is

If 1 + cos x cos y + sin x sin y = 0 , then which of the following is / are true 1. cosx + cosy = 0 2. sinx + siny = 0 3. sinx + cosy = 0 chose the correct option from the code given below

If cosx+cosy+cosz=sinx+siny+sinz=0" then "cos(x-y)=

If cosx + cosy + cosz = 0 = sinx + siny + sinz ,then possible value of cos((x-y)/2) is (A) 4 3 1 2 (B) 4 3 2 1 (C) 3 4 2 1 (D) 3 4 1 2

The solution of the DE cos x (1 + cosy )dx - sin y (1+ sin x ) dy=0 is

ADVANCED MATHS BY ABHINAY MATHS ENGLISH-MOCK TEST - 3 -Multiple Choice Question

Two equal circles intersect so that their centres, and the points at w...
Text Solution
|
PQRA is a rectangle, AP = 22 cm, PQ = 8 cm. DeltaABC is a triangle wh...
Text Solution
|
If cos x. cosy+sinx.siny=-1 then cosx+cosy is :
Text Solution
|
The distance between two pillars is 120 metres. The height of one pill...
Text Solution
|
A hydrogen filled balloon ascending at the rate of 18 kmph was drifted...
Text Solution
|
The angle of elevation of an aeroplane as observed from a point 30 m a...
Text Solution
|
Each member of a club contributes as much rupees and as much paise as ...
Text Solution
|
The numerator of a fraction is multiple of two numbers. One of the num...
Text Solution
|
A number when divided by the sum of 555 and 445 given two times the...
Text Solution
|
A can do a piece of work in 10 days and B can do it in 12 days. They w...
Text Solution
|
The marked price of an article is Rs 5,000. But due to a special festi...
Text Solution
|
The ratio of number of boys to the number of girls in a school of 432,...
Text Solution
|
In two types of brass, the ratios of Copper to Zinc are 8 : 3 and 15 :...
Text Solution
|
In the first 10 overs of a cricket game, the run rate was only 3.2....
Text Solution
|
The average (arithmetic mean) amount of savings of ten students is Rs....
Text Solution
|
If x=1+sqrt""2+sqrt""3, then the value of 2x^(4)-8x^(3)-5x^(2)+26x-28 ...
Text Solution
|
A man buys 3 type-I cakes and 6 type-II cakes for Rs. 900. He sells ty...
Text Solution
|
Due to inclement weather, an air plane reduced its speed by 300 Km/ hr...
Text Solution
|
Three runners A,B and C run a race, with runner A finishing 12 meters ...
Text Solution
|
If the difference of the compound interest and the simple interest on ...
Text Solution
|