共50条信息
若\(a\),\(b\),\(c\)是\(\triangle ABC\)的三边长,请化简\(|a-b-c|+|b-c-a|+|c-a-b|\).
已知:\(A=2{{x}^{2}}+3xy-2x-1\),\(B=-{{x}^{2}}+xy-1\)
\((1)\)求\(3\)\(A\)\(+6\)\(B\)的值;
\((2)\)若\(3\)\(A\)\(+6\)\(B\)的值与\(x\)的值无关,求\(y\)的值。
先化简,再求值:\(x(2x-y)-(x+y) (x-y) + (x-y)\)\({\,\!}^{2}\),其中\(x\)\({\,\!}^{2}\)\(+y\)\({\,\!}^{2}\)\(=5\),\(xy=-2\)\({\,\!}\).
\((1)\)计算:\(( \dfrac{1}{2} )^{-2}+ \sqrt{4} -2\)\(\cos \)\(60^{\circ}\); \((2)\)化简:\((2\)\(a\)\(+1)(2\)\(a\)\(-1)-4(\)\(a\)\(-1)^{2}\)
有一根铁丝长为\(a\)米,第一用去了一半的\(1\)米,第二次用去了剩余部分的一半多\(1\)米,这根铁丝还剩余________米.
化简\((\)\(x\)\(―2)^{2}+(\)\(x\)\(+1)(\)\(x\)\(―1)\)
已知:\(A=2a^{2}+3ab-2a-1\),\(B=-a^{2}+ab-1\).
\((1)\)求\(3A+6B\).
\((2)\)若\(3A+6B\)的值与\(a\)的取值无关,求\(b\)的值.
先化简,再求值:
\((1){x}^{2}+2x-2\left({x}^{2}- \dfrac{1}{2}x\right) \),其中\(x\)\(=1\).
\((2)\)求\(10(\)\(a-b\)\(²)+2(\)\(a-b\)\(²)-9(\)\(a-b\)\(²)\)的值,其中\(a\)\(=1\),\(b\)\(=2\).
进入组卷