dear cma,81is not good.
jinjing
2012-01-02 16:54:15
( reads)
If b=2d,a=20.we get anwser no err.It is 72,71 or 70. If using your formula we get
81.It is not right.A formula should be right in their domain.the (90-a)/b is getting in
times,out is almost the same, so we have 2(90-a)/b times as the ...