\(2a-\left(5-4a\right)+\left(6a-1\right)-\left(2+a\right)\)
\(5a-2b+3-\left(2a-5b+6\right)+\left(a+3b-1\right)\)
\(6x\left(x-1\right)-1\left(6x^2-8x+3\right)=7-\left(x-1\right)\)
\(7x\left(2x-1\right)-\left(14x^2-8x+5\right)=7-\left(-2x+3\right)\)
Thanks các bạn nhiều nha