已知x=2π+1.求(X-1)+(X-2)+(X-3)+(X-4)+(X-5)+(X-6)+(X-7)+(X-8)+(X-9)+(X-10)

问题描述:

已知x=2π+1.求(X-1)+(X-2)+(X-3)+(X-4)+(X-5)+(X-6)+(X-7)+(X-8)+(X-9)+(X-10)

(X-1)+(X-2)+(X-3)+(X-4)+(X-5)+(X-6)+(X-7)+(X-8)+(X-9)+(X-10)
=x-1+x-2+x-3+x-4+x-5+x-6+x-7+x-8+x-9+x-10
=10x-55
=10×(2π+1)-55
=20π+10-55
=20π-45