解
展開する (1−41x)16
解
1−4x+215x2−435x3+64455x4−64273x5+5121001x6−1024715x7+327686435x8−16384715x9+1310721001x10−262144273x11+4194304455x12−419430435x13+3355443215x14−67108864x15+416x16
解答ステップ
(1−41x)16
2項定理を適用する: (a+b)n=i=0∑n(in)a(n−i)bia=1,b=−41x
=i=0∑16(i16)⋅1(16−i)(−41x)i
総和を展開する
=0!(16−0)!16!⋅116(−41x)0+1!(16−1)!16!⋅115(−41x)1+2!(16−2)!16!⋅114(−41x)2+3!(16−3)!16!⋅113(−41x)3+4!(16−4)!16!⋅112(−41x)4+5!(16−5)!16!⋅111(−41x)5+6!(16−6)!16!⋅110(−41x)6+7!(16−7)!16!⋅19(−41x)7+8!(16−8)!16!⋅18(−41x)8+9!(16−9)!16!⋅17(−41x)9+10!(16−10)!16!⋅16(−41x)10+11!(16−11)!16!⋅15(−41x)11+12!(16−12)!16!⋅14(−41x)12+13!(16−13)!16!⋅13(−41x)13+14!(16−14)!16!⋅12(−41x)14+15!(16−15)!16!⋅11(−41x)15+16!(16−16)!16!⋅10(−41x)16
簡素化 0!(16−0)!16!⋅116(−41x)0:1
簡素化 1!(16−1)!16!⋅115(−41x)1:−4x
簡素化 2!(16−2)!16!⋅114(−41x)2:215x2
簡素化 3!(16−3)!16!⋅113(−41x)3:−435x3
簡素化 4!(16−4)!16!⋅112(−41x)4:64455x4
簡素化 5!(16−5)!16!⋅111(−41x)5:−64273x5
簡素化 6!(16−6)!16!⋅110(−41x)6:5121001x6
簡素化 7!(16−7)!16!⋅19(−41x)7:−1024715x7
簡素化 8!(16−8)!16!⋅18(−41x)8:327686435x8
簡素化 9!(16−9)!16!⋅17(−41x)9:−16384715x9
簡素化 10!(16−10)!16!⋅16(−41x)10:1310721001x10
簡素化 11!(16−11)!16!⋅15(−41x)11:−262144273x11
簡素化 12!(16−12)!16!⋅14(−41x)12:4194304455x12
簡素化 13!(16−13)!16!⋅13(−41x)13:−419430435x13
簡素化 14!(16−14)!16!⋅12(−41x)14:3355443215x14
簡素化 15!(16−15)!16!⋅11(−41x)15:−67108864x15
簡素化 16!(16−16)!16!⋅10(−41x)16:416x16
=1−4x+215x2−435x3+64455x4−64273x5+5121001x6−1024715x7+327686435x8−16384715x9+1310721001x10−262144273x11+4194304455x12−419430435x13+3355443215x14−67108864x15+416x16