问题 填空题

设x=y+z=2,则x3+2y3+2z3+6xyz=______.

答案

∵x=y+z=2,

∴x3+2y3+2z3+6xyz

=x3+2y3+2z3+6(y+z)yz

=x3+2(y3+z3+3y2z+3yz2

=x3+2(y+z)3

=23+2×23

=8+16

=24.

故答案为:24.

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