Find the unknown values in the problem involving trigonometry graphs

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chwala
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Homework Statement
see attached
Relevant Equations
trigonometry
My interest is on finding the value of ##A## only. From my calculations, ##A=1##and not ##2## as indicated on textbook solution.
In my working we have; i.e ##4=A +3.##
The values of ##B##and ##C## are correct though. Kindly advise.

Find the question and textbook solution.
1650518637311.png

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Ok I will indeed post my working later. I'll get back on this..finishing on some chores @BvU
 
For tangent graphs, the period is given by;
## Bx= π##,
the period of the given graph is ##x##=##\dfrac {3π}{2}-\dfrac {π}{2}= π##
therefore,
## Bπ= π##, →##B=1##,
The principal axis crosses the y-axis at the point ##(0,3)##, therefore ##C=3##.
Using the given point ##P\left [\frac{π}{4},4\right]##, we shall have,
##y=A tan Bx + C##
##4=A tan \dfrac {π}{4}+3##
##4=A+3##
##A=1##
 
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I agree as well that A = 1. The graph of ##y = 2\tan(x) + 3## would pass through the point ##(\pi/4, 5)## rather than the point P shown on the graph. Also, I find it odd that the problem parameters are A, B, and C, but the posted answer uses a, b, and c. That's sloppy.
 
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