Answer of this question

in my 11th I Do had the same problem But I can just suggest you Go Conceptwise in this app.and even if you do not understand after it ask your school teacher even if it won't work then ask your physics teacher this has same application in chapter waves and Oscillation in 11th class. and for principal solution go Conceptwise of class 12 inverse trigonometry.
Another Thing prepared for graph from R.D It will help you

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Written on May 17, 2019, 9:53 p.m.