Daily Graph 03-08-09

sin π{x}+cos π{x}=1

Where the angle here is in radians....

14 Answers

1
Arshad ~Died~ ·

0≤π{x}<π
so possible values of x are
all integers and all odd integers divided by 2

1
Arshad ~Died~ ·

is that correct sir....??
as this situation is only possible when
π{x}=0 or π{x}=π/2

62
Lokesh Verma ·

why??

Can you tell something more concrete?

1
Arshad ~Died~ ·

π{x}=0 or π{x}=π/2
at only these two point the value of the given function will be 1
so π{x} is 0 at all integral points and at origin only
and π{x} is π/2 only when {x}=1/2 and thats only possible when we divide all odd integers by 2

24
eureka123 ·

did something...
it will be either perfect or disaster :P

2(sin(Ï€4+Ï€{x})=1
=>(sin(Ï€4+Ï€{x})=1/√2

take sin-1
=> π4+π{x}= π4
=>Ï€{x}=0
=>{x}=0

62
Lokesh Verma ·

you have made a small mistake in the last step..

24
eureka123 ·

something related with domain/range naa ??

1
Arshad ~Died~ ·

sir what abt my solution....??????
sir what have i done wrong...????

106
Asish Mahapatra ·

sin π{x}+cos π{x}=1

=> √2 cos(Ï€{x} - Ï€/4) = 1

=> π{x} - π/4 = 2nπ ± π/4

=> {x} = 2n or 2n + 1/2

As {x} = [0,1) So, {x} = 0 or 1/2

=> x = K or K+1/2 where K is an integer

24
eureka123 ·

my mistake was that I didnt write general soln [3]

removing hte hide feature now ..[1]

1
Arshad ~Died~ ·

so my solution was rite too but i just thought about it in a logical way and didnt give any equations..........

1357
Manish Shankar ·

yes yours was right in this case, but avoid doing that, because there might be some cases where you will lose some roots.

go by solving the equations only

1
Arshad ~Died~ ·

thanks for d advice sir.........

1357
Manish Shankar ·

xyz see the asish's solution and compare it

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