函数y=f(x)是什么意思,f(x)不是代表了y吗?y=2x+3可以写成f(x)=2x+3吗?
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y=f(x)的意思是:y是关于x的函数简单情况下,两者一致,可以互相替换。
复杂情况下,一般用需要f(x)而不是y来表示函数关系,y更多的是用来表示纵坐标。
复杂情况是指:
1、函数有多个自变量,此时可能y本身就是自变量,比如f(x,y)=5x+3y
2、同一个自变量,可能有多个函数关系。比如对于x
f(x)=5x+2
g(x)=3x²-27
答1函数y=f(x)的意思
是y是关于x的函数
2f(x)整体是代表了y,
且f(x)有具体的表达式
3y=2x+3可以写成f(x)=2x+3
也可以写成y=f(x)=2x+3
也可以写成y=g(x)=2x+3
f(x)代表的是2x+3这个函数表达式,y代表的是因变量!
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