Diffraction Pattern

Visualize the Intensity distribution pattern due to Fraunhoffer diffraction at single slit if Intensity I=I0 (sinα/α)$2$———–(1) here α=±3π/2,±5π/2, ±7π/2……..±(2n+1)π/2, n=1,2,3,….I0 is the maximum intensity at centre. Distance between 2 consecutive minima x= mλf/a—————(2) Here m-number of minima f- focal length of lens width of slit I=I0 (Sin (3π/2)/3π/2)$2$……gives 4Io/9π$2$……..and so on