(1)
∵a²+b²+c²+338=10a+24b+2bc,
∴a²-10a+25+b²-24b+144+c²-26c+169=0,
∴(a-5)²+(b-12)²+(c-13)²=0,
∴a-5=0,b-12=0,c-13=0,
∴a=5,b=12,c=13.
[PS:2bc应为26c]
(2)
∵根号(a²+64)+|b³-27|=0,
∴(a²-64)=0,|b³-27|=0,
∴a²=64,b³=27,
∴a=±8,b=3,
当a=8,b=3时,
(a-b)b次方的立方根
=[(8-3)^3]的立方根
=8-3
=5,
当a=-8,b=3时,
(a-b)b次方的立方根
=[(-8-3)^3]的立方根
=-8-3
=-11.
[PS:(a²+64)应为(a²-64)]
(3)
4a²+12ab+9b²的算术平方根
=[(2a+3b)²]的算术平方根
=|2a+3b|,
∵a<0,b<0,
∴|2a+3b|
=-(2a+3b)
--2a-3b.
(4)
∵三次根号(1-2X)与三次根号(3Y-2)互为相反数,
∴(1-2X)=-(3Y-2),
∴3Y=1+2X,
∴(1+2X)/Y=3.