Fix precision of BigMath.sin(x,prec) and BigMath.cos(x,prec) for large x #346
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For large x, sin and cos is calculated: sin(x) = sin(x % (2*PI)) cos(x) = cos(x % (2*PI)) When x is large, PI(prec) is not precise enough to calculate `x%(2*PI)`. Extra precision is needed.
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For large x, sin and cos is calculated:
When x is large, PI(prec) is not precise enough to calculate
x%(2*PI). Extra precision is needed.To calculate
BigMath.sin(31415926535, 4),31415926535 % (2 * PI) == 5.385285...needs prec=4.31415926535 % (2 * 3.141) == 1.969...is not enough.31415926535 % (2 * 3.1415926535) == 0is even not enough.31415926535 % (2 * 3.14159265358979) == 5.385is OKPrecision of PI needs to be
>= prec + x.exponent