解答
化简 (1+i)16
解答
256
求解步骤
(1+i)16
使用二项式定理: (a+b)n=i=0∑n(in)a(n−i)bia=1,b=i
=i=0∑16(i16)⋅1(16−i)ii
展开求和
=0!(16−0)!16!⋅116i0+1!(16−1)!16!⋅115i1+2!(16−2)!16!⋅114i2+3!(16−3)!16!⋅113i3+4!(16−4)!16!⋅112i4+5!(16−5)!16!⋅111i5+6!(16−6)!16!⋅110i6+7!(16−7)!16!⋅19i7+8!(16−8)!16!⋅18i8+9!(16−9)!16!⋅17i9+10!(16−10)!16!⋅16i10+11!(16−11)!16!⋅15i11+12!(16−12)!16!⋅14i12+13!(16−13)!16!⋅13i13+14!(16−14)!16!⋅12i14+15!(16−15)!16!⋅11i15+16!(16−16)!16!⋅10i16
化简 0!(16−0)!16!⋅116i0:1
化简 1!(16−1)!16!⋅115i1:16i
化简 2!(16−2)!16!⋅114i2:120i2
化简 3!(16−3)!16!⋅113i3:560i3
化简 4!(16−4)!16!⋅112i4:1820i4
化简 5!(16−5)!16!⋅111i5:4368i5
化简 6!(16−6)!16!⋅110i6:8008i6
化简 7!(16−7)!16!⋅19i7:11440i7
化简 8!(16−8)!16!⋅18i8:12870i8
化简 9!(16−9)!16!⋅17i9:11440i9
化简 10!(16−10)!16!⋅16i10:8008i10
化简 11!(16−11)!16!⋅15i11:4368i11
化简 12!(16−12)!16!⋅14i12:1820i12
化简 13!(16−13)!16!⋅13i13:560i13
化简 14!(16−14)!16!⋅12i14:120i14
化简 15!(16−15)!16!⋅11i15:16i15
化简 16!(16−16)!16!⋅10i16:i16
=1+16i+120i2+560i3+1820i4+4368i5+8008i6+11440i7+12870i8+11440i9+8008i10+4368i11+1820i12+560i13+120i14+16i15+i16
化简 1+16i+120i2+560i3+1820i4+4368i5+8008i6+11440i7+12870i8+11440i9+8008i10+4368i11+1820i12+560i13+120i14+16i15+i16:256
=256