① （-2a-b）^2-(3a-2b)^2② （-1/3t+3）^2+2(1/3t+2)^2③ （3a^2+5）(-3a^2+5)-a^2(7a+4)(7a-4)-16a^2④ （x+2y-m）(x+m+2y)⑤ ( a-1/2)^2(a^2+1/4)^2(a+1/2)^2先化简,再求值：①(a+b)(a-b)^2-2a^2 .其中a=3,b=1/3②（3x+2）(3x-2)-5x(x-1)-

① （-2a-b）^2-(3a-2b)^2② （-1/3t+3）^2+2(1/3t+2)^2③ （3a^2+5）(-3a^2+5)-a^2(7a+4)(7a-4)-16a^2④ （x+2y-m）(x+m+2y)⑤ ( a-1/2)^2(a^2+1/4)^2(a+1/2)^2先化简,再求值：①(a+b)(a-b)^2-2a^2 .其中a=3,b=1/3②（3x+2）(3x-2)-5x(x-1)-
① （-2a-b）^2-(3a-2b)^2
② （-1/3t+3）^2+2(1/3t+2)^2
③ （3a^2+5）(-3a^2+5)-a^2(7a+4)(7a-4)-16a^2
④ （x+2y-m）(x+m+2y)
⑤ ( a-1/2)^2(a^2+1/4)^2(a+1/2)^2
先化简,再求值：①(a+b)(a-b)^2-2a^2 .其中a=3,b=1/3
②（3x+2）(3x-2)-5x(x-1)-(2x-1)^2.其中x=1/3
三、如果(-5a+M)(4b+N)=(166^2)-(25a^2)
四、已知M=x^2+5ax-x-1,N=-2x^2+ax-1

① （-2a-b）^2-(3a-2b)^2② （-1/3t+3）^2+2(1/3t+2)^2③ （3a^2+5）(-3a^2+5)-a^2(7a+4)(7a-4)-16a^2④ （x+2y-m）(x+m+2y)⑤ ( a-1/2)^2(a^2+1/4)^2(a+1/2)^2先化简,再求值：①(a+b)(a-b)^2-2a^2 .其中a=3,b=1/3②（3x+2）(3x-2)-5x(x-1)-
① （-2a-b）^2-(3a-2b)^2=4a^2+4ab+b^2-9a^2+12ab-4b^2=-5a^2+16ab-3b^2
② （-1/3t+3）^2+2(1/3t+2)^2=t^2/9-2t+9+2(t^2/9+4t/3+4)=t^2/3+2t/3+17
③ （3a^2+5）(-3a^2+5)-a^2(7a+4)(7a-4)-16a^2=25-9a^4-49a^4+16a^2-16a^2=25-58a^4
④ （x+2y-m）(x+m+2y)=x^2+4yx+4y^2-m^2
⑤ ( a-1/2)^2(a^2+1/4)^2(a+1/2)^2= ( a-1/2)^2(a+1/2)^2(a^2+1/4)^2=(a^2-1/4)^2(a^2+1/4)^2=(a^4-1/16)^2=a^8-a^4/8+1/256
先化简,再求值： ①(a+b)(a-b)^2-2a^2 .其中a=3,b=1/3
①(a+b)(a-b)^2-2a^2 =(a^2-b^2)(a-b)-2a^2=a^3-ab62-a^2b+b^3-2a^2=6-8/27=154/27
②（3x+2）(3x-2)-5x(x-1)-(2x-1)^2.其中x=1/3
②（3x+2）(3x-2)-5x(x-1)-(2x-1)^2=9x^2-4-5x^2+5x-4x^2+4x-1=9x-5=3-5=-2
后面的不完整,没有办法算了

额

一
(1)原式=（-2a-b+3a-2b）(-2a-b-3a+2b)=(a-3b)(-5a+b)=-5a^2+16ab-3b^2
(2)原式=1/9t^2-2t+9+2/9t^2+8/3t+8=1/3t^2+2/3t+17
(3)原式=25-9a^4-a^2(49a^2-16）-16a^2=25-9a^4-49a^4+16a^2-16a^2=25-58a^4
(4)...

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一
(1)原式=（-2a-b+3a-2b）(-2a-b-3a+2b)=(a-3b)(-5a+b)=-5a^2+16ab-3b^2
(2)原式=1/9t^2-2t+9+2/9t^2+8/3t+8=1/3t^2+2/3t+17
(3)原式=25-9a^4-a^2(49a^2-16）-16a^2=25-9a^4-49a^4+16a^2-16a^2=25-58a^4
(4)原式=(x+2y)^2-m^2=x^2+4xy+4y^2-m^2
(5)原式=((a-1/2)(a+1/2))^2(a^2+1/4)^2=(a^2-1/4)^2(a^2+1/4)^2=((a^2-1/4)(a^2+1/4))^2=(a^4-1/16)^2=a^8-1/8a^4+1/256
二。（1）原式=（a+b）(a-b)(a-b)=(a^2-b^2)(a-b)=a^3-a^2b-b^2a-b^3,代入数值可得：27-3-1/3-1/27=638/27
(2)原式=9x^2-4-5x^2+5x-4x^2+4x-1=9x-5=-2
三、题目能说的详细点吗？我没看懂

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1. 原式=4a^2+4ab+b^2-(9a^2-12ab+4b^2)
=-5a^2+16ab-5b^2
2. 原式=1/9t^2-2t+9+2(1/9t^2+4/3t+4)
=1/9t^2-2t+9+2/9t^2+8/3t+8
=1/3t^2+2/3t+17
3. 原式=-(3a...

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1. 原式=4a^2+4ab+b^2-(9a^2-12ab+4b^2)
=-5a^2+16ab-5b^2
2. 原式=1/9t^2-2t+9+2(1/9t^2+4/3t+4)
=1/9t^2-2t+9+2/9t^2+8/3t+8
=1/3t^2+2/3t+17
3. 原式=-(3a^2+5)(3a^2-5)-a^2(49a^2-16)-16a^2
=-(9a^4-25)-49a^4+16a^2-16a^2
=-58a^4+25
4.原式=(x+2y)^2-m^2
=x^2+4xy+4y^2-m^2
5.原式=（a-1/2)^2(a+1/2)^2(a^2+1/4)^2
=[(a-1/2)(a+1/2)]^2(a^2+1/4)^2
=(a^2-1/4)^2(a^2+1/4)^2
=(a^4-1/16)^2
=a^8-1/8a^4+1/256

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