Question

若5的n次方乘x的n+1次方乘yz的n次方是八次单项式,则n的值为( )

Answer 1

5^n*x^(n+1)*(yz)^n

=5^n*x^(n+1)*y^n*z^n

5^n是常数,不算在单项式的次数内

所以此单项式次数是(n+1)+n+n=8

3n+1=8

n=7/3

选A