由欧拉公式,e^(wτ+π/4)j的实部是()
A: tg(wτ+π/4)
B: sin(wτ+π/4)
C: cos(wτ+π/4)
D: ctg(wτ+π/4)
A: tg(wτ+π/4)
B: sin(wτ+π/4)
C: cos(wτ+π/4)
D: ctg(wτ+π/4)
举一反三
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