echo "asinh(1) = ", asinh(1) . "<br />";
echo "asinh(0) = ", asinh(0) . "<br />";
echo "asinh(10) = ", asinh(10) . "<br />";
echo "asinh(0.5) = ", asinh(0.5) . "<br />";
/*
run:
asinh(1) = 0.88137358701954
asinh(0) = 0
asinh(10) = 2.998222950298
asinh(0.5) = 0.4812118250596
*/