Toán Lớp 9: 2x-1)căn(10-4x^2)=5-2x hứa lời trả lời hay nhất + 5 sao

Question

Toán Lớp 9:  2x-1)căn(10-4x^2)=5-2x hứa lời trả lời hay nhất + 5 sao

baoquyen · Answer

(2x-1).&radic;10-4x&sup2;=5-2x   &rarr; (2x-1)&sup2;.(10-4x&sup2;)=25-20x+4x&sup2;   &rarr;(4x&sup2;-4x+1).(10-4x&sup2;)=25-20x+4x&sup2;   &rarr;40x&sup2;-$16x^{4}$-40x+16x&sup3;+10-4x&sup2;=25-20x+4x&sup2;   &rarr;36x&sup2;-$16x^{4}$ -40x+16x&sup3;+10=25-20x+4x&sup2;   &rarr;36x&sup2;-$16x^{4}$ -40x+16x&sup3;+10-25+20x-4x&sup2; = 0   &rarr;32x&sup2;-$16x^{4}$ -20x+16x&sup3;-15=0   &rarr;$-16x^{4}$ -8x&sup3;+24x&sup3;+12x&sup2;+20x&sup2;+10x-30x-15=0   &rarr;-8x&sup3;(2x+1)+12x&sup2;(2x+1)+10x(2x+1)-15(2x+1)=0   &rarr;-(2x+1)[4x&sup2;(2x-3)-5(2x-3)]=0   &rarr;-(2x+1)(2x-3)(4x&sup2;-5)=0   &rarr;(2x+1)(2x-3)(4x&sup2;-5)=0   2x+1=0 &rArr; x=-$ frac{1}{2}$    2x-3=0 &rArr; x=$ frac{3}{2}$    4x&sup2;-5+0 &rArr; x=-$ frac{&radic;5}{2}$ , x=$ frac{5}{2}$    @giahanchau