数学习题三道 1.已知a=2,b=-1,c=-3时.求(a+b+c)^2=?a^2+b^2+c^2+2ab+2ac=?2.已知a-1/a=2,求(a-1/a)^2-1/a+6+a的值3.已知a=-1/b,b=4,c=-3,求3a+(a^2)b(c^2)-1/3c^2-3ab+1/3c^3
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![数学习题三道 1.已知a=2,b=-1,c=-3时.求(a+b+c)^2=?a^2+b^2+c^2+2ab+2ac=?2.已知a-1/a=2,求(a-1/a)^2-1/a+6+a的值3.已知a=-1/b,b=4,c=-3,求3a+(a^2)b(c^2)-1/3c^2-3ab+1/3c^3](/uploads/image/z/4519602-18-2.jpg?t=%E6%95%B0%E5%AD%A6%E4%B9%A0%E9%A2%98%E4%B8%89%E9%81%93+1.%E5%B7%B2%E7%9F%A5a%3D2%2Cb%3D-1%2Cc%3D-3%E6%97%B6.%E6%B1%82%28a%2Bb%2Bc%29%5E2%3D%3Fa%5E2%2Bb%5E2%2Bc%5E2%2B2ab%2B2ac%3D%3F2.%E5%B7%B2%E7%9F%A5a-1%2Fa%3D2%2C%E6%B1%82%EF%BC%88a-1%2Fa%29%5E2-1%2Fa%2B6%2Ba%E7%9A%84%E5%80%BC3.%E5%B7%B2%E7%9F%A5a%3D-1%2Fb%2Cb%3D4%2Cc%3D-3%2C%E6%B1%823a%2B%28a%5E2%29b%28c%5E2%29-1%2F3c%5E2-3ab%2B1%2F3c%5E3)
数学习题三道 1.已知a=2,b=-1,c=-3时.求(a+b+c)^2=?a^2+b^2+c^2+2ab+2ac=?2.已知a-1/a=2,求(a-1/a)^2-1/a+6+a的值3.已知a=-1/b,b=4,c=-3,求3a+(a^2)b(c^2)-1/3c^2-3ab+1/3c^3
数学习题三道 1.已知a=2,b=-1,c=-3时.求(a+b+c)^2=?a^2+b^2+c^2+2ab+2ac=?
2.已知a-1/a=2,求(a-1/a)^2-1/a+6+a的值
3.已知a=-1/b,b=4,c=-3,求3a+(a^2)b(c^2)-1/3c^2-3ab+1/3c^3
数学习题三道 1.已知a=2,b=-1,c=-3时.求(a+b+c)^2=?a^2+b^2+c^2+2ab+2ac=?2.已知a-1/a=2,求(a-1/a)^2-1/a+6+a的值3.已知a=-1/b,b=4,c=-3,求3a+(a^2)b(c^2)-1/3c^2-3ab+1/3c^3
(a+b+c)^2=(2-1-3)^2=4
a^2+b^2+c^2+2ab+2ac=2^2+(-1)^2+(-3)^2+2*2*(-1)+2*2*(-3)=4+1-4-12=-11
a-1/a=2,
(a-1/a)^2-1/a+6+a=(a-1/a)^2+a-1/a+6=2^2+2+6=12
a=-1/b,b=4,c=-3,
a=-1/4
3a+(a^2)b(c^2)-1/3c^2-3ab+1/3c^3
=3*(-1/4)+(-1/4)*4*(-3)^2)-1/3*(-3)^2-3(-1/4)*4+1/3(-3)^3
=-3/4-9-1/3+3+9
=2-1/12