Solving a problem in physics section 4 point 5 optics

Solving a problem in physics section 4 point 5 optics

5. grating normally incident beam of light from the discharge tube. What should be equal to a constant grating in a direction to φ = 410 match a maximum of two lines: λ1 = 6563 Ǻ and λ2 = 4102 Ǻ? It is known that the maximum order of the spectrum of the lattice in the visible light (400 700 nm) kmax = 12

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Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)