(2+x)^5=a0+a1(x-1)+a2(x-1)^2+a3(x-1)^3+a4(x-1)^4+a5(x-1)^5则a1+a3+a5=?急
问题描述:
(2+x)^5=a0+a1(x-1)+a2(x-1)^2+a3(x-1)^3+a4(x-1)^4+a5(x-1)^5则a1+a3+a5=?急
答
(2+x)^5=a0+a1(x-1)+a2(x-1)^2+a3(x-1)^3+a4(x-1)^4+a5(x-1)^5令x-1=1,即x=2得4^5=a0+a1+a2+a3+a4+a5=1024令x-1=-1即x=0得2^5=a0-a1+a2-a3+a4-a5=512两式相减:2(a1+a3+a5)=512∴a1+a3+a5=2562 ^5=512?(哈哈莫名其妙)4^5=a0+a1+a2+a3+a4+a5=1024令x-1=-1即x=0得 2^5=a0-a1+a2-a3+a4-a5=32两式相减:2(a1+a3+a5)=992 ∴a1+a3+a5=496