一条高数的题帮我解下!用换元法!
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/07/29 22:30:48
一条高数的题帮我解下!用换元法!
设f(x+1)=x(x+1),则f(x)=?
t=x?
设f(x+1)=x(x+1),则f(x)=?
t=x?
![一条高数的题帮我解下!用换元法!](/uploads/image/z/17679000-48-0.jpg?t=%E4%B8%80%E6%9D%A1%E9%AB%98%E6%95%B0%E7%9A%84%E9%A2%98%E5%B8%AE%E6%88%91%E8%A7%A3%E4%B8%8B%21%E7%94%A8%E6%8D%A2%E5%85%83%E6%B3%95%21)
设x+1=t
则x=t-1
x(x+1)=(t-1)*(t-1+1)=t(t-1)
则f(t)=t*(t-1)
既f(x)=x(x-1)
则x=t-1
x(x+1)=(t-1)*(t-1+1)=t(t-1)
则f(t)=t*(t-1)
既f(x)=x(x-1)