Question

When axes are rotated through an angle of 45° in positive direction without changing origin then
the coordinates of (^2,4) in old system are​

Answer 1

Explanation:

When axes are rotated through an angle θ, then co-ordinates are

x=xcosϕ−ysinϕ=

2

x

−

2

y

=

2

2

−

2

4

=1−2

2

y=xsinϕ+ycosϕ=

2

x

+

2

y

=

2

2

+

2

4

=1+2

2

∴ co-ordinates are (1−2

2

,1+2

2

)