x+9=0 hoạc x-3=0 hoạc x+21=0
x=-9 hoạc x=3 hoac x=-21
\(15\left(x+9\right)\left(x-3\right)\left(x+21\right)=0\\ \Leftrightarrow\left(x+9\right)\left(x-3\right)\left(x+21\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x+9=0\\x-3=0\\x+21=0\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=-9\\x=3\\x=-21\end{matrix}\right.\)
VẬy...
15(x+9)(x-3)(x+21)=0
15(x+9)(x-3)(x+21)
giai ho mik nhe
a) 5x + 6 = 0
b) 9x - 3 = 6x + 21
c) x^3 - 9x = 0
d) 1/x-2 - x^2 -4 /4-x^2= 0
Làm bài 21 phần e và f
\(\left(2x-5\right)^2\)- \(\left(x+2\right)^2\) = 0
\(x^2-x-\left(3x-3\right)=0\)
Bài 5: Giải phương trình
a) x ( x+1) ( x – 1) ( x+2) =24
b) ( x – 4) ( x – 5) ( x – 6) ( x – 7) = 1680
c) 2x ( 8x – 1) 2 ( 4x – 1) = 9
d) ( 2x + 1)( x + 1) 2 ( 2x + 3) = 18
e) (x 2 – 6x +9 ) 2 – 15( x 2 – 6x +10) = 1
f) ( x 2 + 1) 2 + 3x ( x 2 + 1) + 2x 2 = 0
g) ( x 2 – 9) 2 = 12x + 1
Bài 6: Giải phương trình
a) ( x + 3) 4 + ( x+ 5 ) 4 = 16
b) ( x – 2) 4 + ( x – 3) 4 = 1
Bài 5: Giải phương trình
a) x ( x+1) ( x – 1) ( x+2) =24
b) ( x – 4) ( x – 5) ( x – 6) ( x – 7) = 1680
c) 2x ( 8x – 1) 2 ( 4x – 1) = 9
d) ( 2x + 1)( x + 1) 2 ( 2x + 3) = 18
e) (x 2 – 6x +9 ) 2 – 15( x 2 – 6x +10) = 1
f) ( x 2 + 1) 2 + 3x ( x 2 + 1) + 2x 2 = 0
g) ( x 2 – 9) 2 = 12x + 1
Bài 6: Giải phương trình
a) ( x + 3) 4 + ( x+ 5 ) 4 = 16
b) ( x – 2) 4 + ( x – 3) 4 = 1
Giải phương trình:
10. (x2-2x-3)(x2+10x+21)=25
11. x4-4x3+10x2+37x-14=0
12. (x+5)(x+10)(x+11)-8x=0
a,x^2-9x+20=0
b,x^3-4x^2+5x=0
c,x^2=2x-15=0
d,(x^2-1)^2=4x+1
e,4x^3-9x^2+6x-1=0
f,x^4-4x^3-x^2+16x-12=0
(X^2-6x+9)^2-15(x^2-6x+10)=1
(X^2+1)^2+3x (x^2+1)+2x^2=0
