Set m is the function y=cos? x-sin？ X = the range of cos (2x), then:

M={y|- 1≤y≤ 1}、N = { x |- 1 & lt； x & lt 1}

m∩N = { x |- 1 & lt； x & lt 1}

Since x is a real number, the modulus of x-I is:

|x-i|=√(x？ + 1)

Then:

| x-I | & lt； √2

√(x？ + 1)& lt； √2

x？ + 1 & lt； 2

x？ & lt 1

Then:

- 1 & lt； x & lt 1

Namely: n = {x |- 1