Mysterious Trig Function
Given the graph above of
for integers
and
find
The answer is -1.
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1 solution
Moderator note:
Good usage of the various characteristics of the graph to determine these values.
The amplitude of this graph is A 2 + B 2 = 5 . We also have y ( 0 ) = A sin ( 0 ) + B cos ( 0 ) = B = 4 . Thus, B = 4 and A = ± 3 .
To determine the sign of A we can look at y ( 2 π ) . It is clearly positive, so A = 3 . Thus, A − B = 3 − 4 = − 1 .