化简2s/s÷a+s÷b

2、Where’s John?.A:He’s sleeping.B:She’s sleeping.C:He’s slee 利用余弦定理证明海伦公式S=√[s(s-a)(s-b)(s-c)]. C语言编程,三角形面积的海伦公式为：area=开根号[s(s-a)(s-b)(s-c],其中s=(a+b+c)/2,a、 what's this?A.It's here B.It's the letter S C .its S D.It's 在公s+a/s+b-b/s=1中,a、b已知且a不等于2b,求s S B S J B ___hot and sunny.__no wind.A.It's...There's B.Today's...It's Whese's Johm? A He's sleeping. B She's sleeping. c He's slee 求三角型面积公式推导 area=sqrt（s*(s-a)*(s-b)*(s-c)) √s*(s-a)*(s-b)*(s-c) 请问大家这个数学公式是求什么的? ----his sister. A.He's B.this's C.that's D.who's He is a old friend of Asmise “s brother 's B brother 's of S