d*sin(θ)=m*λ

sin(θ)≈tan(θ)=(x_i)/l

(d*(x_i))/l≈d*sin(θ)=m*λ

d=0.125⋅10

λ=650⋅10

l=71.0⋅10

m=1

(x_i)≈(l*m*λ)/d=((71⋅10)*(1)*(650⋅10))/(0.125⋅10)=3.69⋅10=0.369

θ=arctan((x_i)/l)=arctan((3.9⋅10)/(71.0⋅10))=0.31

θ≤0.748

m=(d*sin(θ))/λ≤(d*sin(0.748))/λ=2.5

⇒m≥-2.5

⇒m∈<-2,-1,0,1,2>