f(z）=2z+z'-3i f(z'+i)=6-3i,则f(-z)=?我知道答案是-6-4i,大概过程我也明白,但没算明白,_数学解答

f(z）=2z+z'-3i f(z'+i)=6-3i,则f(-z)=?
我知道答案是-6-4i,大概过程我也明白,但没算明白,

人气：202 ℃　时间：2020-05-13 01:33:20

解答

因为f(z）=2z+z'-3i,把z'+i代入有：f(z'+i）=2(z'+i)+(z-i)-3i=6-3i
所以2z'+z+i=6
所以2z'+z=6-i
所以2z+z'=6+i
f(-z)=-2z-z'-3i=-6-i-3i=-6-4i