Question

If a cos 0 -b sin 0 = x and a sin 0+ bcos 0 = y, prove that a +b = x + y.​

Answer 1

ANSWER

$<strong><em><u>we \: know \: that</u></em></strong> \\ \cos(0) = 1 \\ \sin(0) = 0\\ i)a \cos(0) - b \sin(0) = x \\ a = x \\ <strong><em><u>now</u></em></strong> \\ ii)a \sin(0) + b \cos(0) = y \\ b = y \\ <strong><em><u>therefore</u></em></strong> \\ a + b = x + y \: \: \: \: (proved)$

Answer 2

cos(0)=1

sin(0)=0

i)acos(0)−bsin(0)=x

a=x

now

ii)asin(0)+bcos(0)=y

b=y

therefore

a+b=x+y(proved)