已知实数a,b,c满足｜a+1｜+（b-5）^2+(25c^2+10c+1)=0,求(abc)^251/(a^11b^8c^7)的值
∵｜a+1｜+（b-5）^2+(25c^2+10c+1)=0
｜a+1｜+（b-5）^2+(5c+1)²=0
∴a+1=0 b-5=0 5c+1=0
a=-1 b=5 c=-1/5
∴(abc)^251/(a^11b^8c^7)
=(abc)^251/[a^11b(bc)^7]
=(-1*5*-1/5)^251/[(-1)^11*5*(5*-1/5)^7]
=1/5
-3x^2y^3*(-2x²yz²)÷2（x³z）y^3=3xyz 使等式成立