CosA+sinA=1 prove that cosA-sinA=+-1
Answers
Answered by
3
CosA +SinA =1.=> on squaring on both sides we get
CosA^2+SinA^2+2SinACosA=1 => 2SinACosA =1-SinA^2-CosA^2=0..(1)since SinA^2+CosA^2 =1. now let's take x=CosA-SinA now squaring on both sides ,
x^2=CosA^2+ SinA^2-2SinACosA =1-0(from(1)) =1.So on applying square root on both sides , we get x=1 or -1 .CosA +SinA=+-1 .Hence proved .Hope it helps you...
CosA^2+SinA^2+2SinACosA=1 => 2SinACosA =1-SinA^2-CosA^2=0..(1)since SinA^2+CosA^2 =1. now let's take x=CosA-SinA now squaring on both sides ,
x^2=CosA^2+ SinA^2-2SinACosA =1-0(from(1)) =1.So on applying square root on both sides , we get x=1 or -1 .CosA +SinA=+-1 .Hence proved .Hope it helps you...
Answered by
2
Step-by-step explanation:
waiting for you
come to my question yrrr plzz I want to talk to you
Similar questions