1.(-2a(a头上三次方))bc)²*(-ab²)三次方;2.(4.5*10的五次方)(2*10的三次方)(3*10的四次方);3.2x²y*(-8y²)+4x²y*5y²;4.(x+3y)(2x-y);5.3x(x²-2x-1)-2x²(x-3);6.先化简,再求值:2(x+5)(x-4)-3(x-6)(x+1),其中x=2;7.16-(2a+3b)²;8.-36x²+12xy-y²;9.4x(a-b)-8y(b-a);10.(x²-5)²+8(x²-5)+16前面 例:1.等是题号 不要跟题目混了

问题描述:

1.(-2a(a头上三次方))bc)²*(-ab²)三次方;2.(4.5*10的五次方)(2*10的三次方)(3*10的四次方);3.2x²y*(-8y²)+4x²y*5y²;4.(x+3y)(2x-y);5.3x(x²-2x-1)-2x²(x-3);6.先化简,再求值:2(x+5)(x-4)-3(x-6)(x+1),其中x=2;7.16-(2a+3b)²;8.-36x²+12xy-y²;9.4x(a-b)-8y(b-a);10.(x²-5)²+8(x²-5)+16
前面 例:1.等是题号 不要跟题目混了

1. (-2a(a头上三次方))bc)²*(-ab²)三次方;
(-2a^3bc)^2*(-ab^2)
=4a^6b^2c^2*(-ab^2)
=-4a^7b^4c^2
2.(4.5*10的五次方)(2*10的三次方)(3*10的四次方);
(4.5*10^5)(2*10^3)(3*10^4)
=(4.5*2*3)*10^(5+3+4)
=27*10^12
=2.7*10^13
3. 2x²y*(-8y²)+4x²y*5y²;
=-16x^2y^3+4x^2y^3
=-12x^2y^3
4.(x+3y)(2x-y);
=2x^2+5xy-3y^2
5. 3x(x²-2x-1)-2x²(x-3);
=3x^3-6x^2-3x-2x^3+6x^2
=x^3-3x
=x(x^2-3)
6.先化简,再求值:
2(x+5)(x-4)-3(x-6)(x+1),其中x=2;
=2(x^2+x-20)-3(x^2-5x-6)
=2x^2+2x-40-3x^2+15x-18
=-x^2+17x-58
=-2^2+17*2-58
=-4+34-58
=-28
7. 16-(2a+3b)²;
=(4-2a-3b)(4+2a+3b)
8.-36x²+12xy-y²;
=-(36x²-12xy+y²)
=-(6x-y)²
9. 4x(a-b)-8y(b-a);
=4x(a-b)+8y(a-b)
=4(a-b)(x+2y)
10.(x²-5)²+8(x²-5)+16
=(x²-5-4)²
=(x²-9)²
=[(x-3)(x+3)]²
=(x-3)²(x+3)²