Bạn tham khảo:$( 2-3x )( x + 11 ) = ( 3x - 2 )( 2 - 5x )$ $⇔ ( 2 - 3x )(x +11) + ( 2 -3x )( 2 - 5x )=0$ $⇔ ( 2 - 3x )( x + 11 + 2 - 5x ) = 0$$⇔ ( 2 - 3x )( 13 - 4x ) = 0$$⇔$ \(\left[ \begin{array}{l}x=\dfrac{2}{3}\\x=\dfrac{13}{4}\end{array} \right.\)
(2-3x)(x+11)=(3x-2)(2-5x)
⇔ (2-3x)(x+11)= -(2 -3x)(2-5x)
⇔ (2-3x)(x+11) + (2 -3x)(2-5x) = 0
⇔ (2 -3x).(x +11 +2 -5x) = 0
⇔ (2 -3x).(-4x +13) = 0
⇔ 2 -3x = 0 hoặc -4x +13 = 0
⇔ -3x = -2 hoặc -4x = -13
⇔ x = 2/3 hoặc x = 13/4
Vậy S= {2/3; 13/4}
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Tìm tất cả các giá trị thực của tham số m để hàm số f (x)=căn của (m+4)x2-(m- 4)x-2m+1 xác định với mọi x thuộc R
Giúp mình với mình sẽ vote 5 sao
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