计算:[(2a+b)(2a-b)-4(a-2b)²+4b(a-2b)]÷(-4b)[(-3mn)²×m³-2m³(3mn²)³×½n]÷(-3m³n)²解方程:x(9x-5)-(3x-1)(3x+1)=56x+7(2x+3)(2x-3)-28(x-½)(x+½
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计算:[(2a+b)(2a-b)-4(a-2b)²+4b(a-2b)]÷(-4b)[(-3mn)²×m³-2m³(3mn²)³×½n]÷(-3m³n)²解方程:x(9x-5)-(3x-1)(3x+1)=56x+7(2x+3)(2x-3)-28(x-½)(x+½
计算:[(2a+b)(2a-b)-4(a-2b)²+4b(a-2b)]÷(-4b)
[(-3mn)²×m³-2m³(3mn²)³×½n]÷(-3m³n)²
解方程:x(9x-5)-(3x-1)(3x+1)=5
6x+7(2x+3)(2x-3)-28(x-½)(x+½)=4
计算:[(2a+b)(2a-b)-4(a-2b)²+4b(a-2b)]÷(-4b)[(-3mn)²×m³-2m³(3mn²)³×½n]÷(-3m³n)²解方程:x(9x-5)-(3x-1)(3x+1)=56x+7(2x+3)(2x-3)-28(x-½)(x+½
1.[(2a+b)(2a-b)-4(a-2b)^2+4b(a-2b)]÷(-4b)
=[4a^2-b^2-4a^2+16ab-16b^2+4ab-8b^2]/(-4b)
=(20ab-25b^2)/(-4b)
=25b/4-5a
2.[(-3mn)^2×m^3-2m^3(3mn^2)^3*1/2n]÷(-3m^3n)^2
=(9m^5n^2-3m^4n^7)/(9m^6n^2)
=1/m-n^5/3m^2.
3.x(9x-5)-(3x-1)(3x+1)=5
9x^2-5x-9x^2+1=5
5x=-4
x=-4/5
4.6x+7(2x+3)(2x-3)-28(x-1/2)(x+1/2)=4
6x+28x^2-63-28x^2+7=4
6x=60
x=10