Câu trong ảnh làm như nào các bạn ơi... Bài 2: Triển khai các biểu thức sau theo hằ *ẳng thức T,

$1)~x^2-4$,$2)~1-4x^2$,$3)~4x^2-9$
$4)~9-25x^2$,$5)~4x^2-25$,$6)~9x^2-36$
$7)~(3x)^2-y^2$,$8)~x^2-(2y)^2$,$9)~(2x)^2-y^2$
$10)~(3x)^2-9y^4$,$11)16x^2-(y^2)^2$,$12)~x^4-(3y^2)^2$
$13)~(x-1)(x+1)$,$14)(x-5)(x+5)$,$15)(x-6)(6+x)$
$16)~(2x+1)(2x-1)$,$17)(x-2y)(2y+x)$,$18)(5x-3y)(3y+5x)$
$19)(\frac1x-5)(\frac1x+5)$,$20)~(x-\frac32)(x+\frac32)$,$21)(\frac x3-\frac y4)(\frac x3+\frac y4)$
$22)(\frac xy-\frac23)(\frac xy+\frac23)$,$23)(\frac x2+\frac y3)(\frac y3-\frac x2)$,$24)(2x-\frac23)(\frac23+2x)$

Question

Câu trong ảnh làm như nào các bạn ơi... Bài 2: Triển khai các biểu thức sau theo hằ *ẳng thức T,

$1)~x^2-4$,$2)~1-4x^2$,$3)~4x^2-9$
$4)~9-25x^2$,$5)~4x^2-25$,$6)~9x^2-36$
$7)~(3x)^2-y^2$,$8)~x^2-(2y)^2$,$9)~(2x)^2-y^2$
$10)~(3x)^2-9y^4$,$11)16x^2-(y^2)^2$,$12)~x^4-(3y^2)^2$
$13)~(x-1)(x+1)$,$14)(x-5)(x+5)$,$15)(x-6)(6+x)$
$16)~(2x+1)(2x-1)$,$17)(x-2y)(2y+x)$,$18)(5x-3y)(3y+5x)$
$19)(\frac1x-5)(\frac1x+5)$,$20)~(x-\frac32)(x+\frac32)$,$21)(\frac x3-\frac y4)(\frac x3+\frac y4)$
$22)(\frac xy-\frac23)(\frac xy+\frac23)$,$23)(\frac x2+\frac y3)(\frac y3-\frac x2)$,$24)(2x-\frac23)(\frac23+2x)$

minhchinhs · Accepted Answer

{"userId":5168711,"userName":"Hữu Hiền Minh Nguyễn"}

1)$x^2 - 4 = x^2 - 2^2 = (x - 2)(x + 2)$

2) $1 - 4x^2 = 1^2 - (2x)^2 = (1 - 2x)(1 + 2x)$

3) $4x^2 - 9 = (2x)^2 - 3^2 = (2x - 3)(2x + 3)$

4) $9 - 25x^2 = 3^2 - (5x)^2 = (3 - 5x)(3 + 5x)$

5) $4x^2 - 25 = (2x)^2 - 5^2 = (2x - 5)(2x + 5)$

6) $9x^2 - 36 = (3x)^2 - 6^2 = (3x - 6)(3x + 6)$

7) $(3x)^2 - y^2 = (3x - y)(3x + y)$

8) $x^2 - (2y)^2 = (x - 2y)(x + 2y)$

9) $(2x)^2 - y^2 = (2x - y)(2x + y)$

10) $(3x)^2 - 9y^4 = 9x^2 - (3y^2)^2 = (3x - 3y^2)(3x + 3y^2)$

11) $16x^2 - (y^2)^2 = (4x)^2 - y^4 = (4x - y^2)(4x + y^2)$

12) $x^4 - (3y^2)^2 = x^4 - 9y^4 = (x^2 - 3y^2)(x^2 + 3y^2)$

13) $(x - 1)(x + 1) = x^2 - 1$

14) $(x - 5)(x + 5) = x^2 - 25$

15) $(x - 6)(x + 6) = x^2 - 36$

16) $(2x + 1)(2x - 1) = (2x)^2 - 1 = 4x^2 - 1$

17) $(x - 2y)(x + 2y) = x^2 - (2y)^2 = x^2 - 4y^2$

18) $(5x - 3y)(5x + 3y) = (5x)^2 - (3y)^2 = 25x^2 - 9y^2$

19) $\left( \frac{1}{x} - 5 \right)\left( \frac{1}{x} + 5 \right) = \left( \frac{1}{x} \right)^2 - 25 = \frac{1}{x^2} - 25$

20) $\left( x - \frac{3}{2} \right)\left( x + \frac{3}{2} \right) = x^2 - \left( \frac{3}{2} \right)^2 = x^2 - \frac{9}{4}$

21) $\left( \frac{x}{3} - \frac{y}{4} \right)\left( \frac{x}{3} + \frac{y}{4} \right) = \left( \frac{x}{3} \right)^2 - \left( \frac{y}{4} \right)^2 = \frac{x^2}{9} - \frac{y^2}{16}$

22) $\left( \frac{x}{y} - \frac{2}{3} \right)\left( \frac{x}{y} + \frac{2}{3} \right) = \left( \frac{x}{y} \right)^2 - \left( \frac{2}{3} \right)^2 = \frac{x^2}{y^2} - \frac{4}{9}$

23) $\left( \frac{x}{2} + \frac{y}{3} \right)\left( \frac{y}{3} - \frac{x}{2} \right) = \left( \frac{x}{2} \right)^2 - \left( \frac{y}{3} \right)^2 = \frac{x^2}{4} - \frac{y^2}{9}$

24) $(2x - \frac{2}{3})(2x + \frac{2}{3}) = (2x)^2 - \left( \frac{2}{3} \right)^2 = 4x^2 - \frac{4}{9}$

Timi · Answer

Bài 2:
1) $ x^2 - 4 = x^2 - 2^2 = (x - 2)(x + 2) $

2) $ 1 - 4x^2 = 1 - (2x)^2 = (1 - 2x)(1 + 2x) $

3) $ 4x^2 - 9 = (2x)^2 - 3^2 = (2x - 3)(2x + 3) $

4) $ 9 - 25x^2 = 3^2 - (5x)^2 = (3 - 5x)(3 + 5x) $

5) $ 4x^2 - 25 = (2x)^2 - 5^2 = (2x - 5)(2x + 5) $

6) $ 9x^2 - 36 = (3x)^2 - 6^2 = (3x - 6)(3x + 6) $

7) $ (3x)^2 - y^2 = 9x^2 - y^2 = (3x - y)(3x + y) $

8) $ x^2 - (2y)^2 = x^2 - 4y^2 = (x - 2y)(x + 2y) $

9) $ (2x)^2 - y^2 = 4x^2 - y^2 = (2x - y)(2x + y) $

10) $ (3x)^2 - 9y^4 = 9x^2 - 9y^4 = 9(x^2 - y^4) = 9(x^2 - (y^2)^2) = 9(x - y^2)(x + y^2) $

11) $ 16x^2 - (y^2)^2 = (4x)^2 - (y^2)^2 = (4x - y^2)(4x + y^2) $

12) $ x^4 - (3y^2)^2 = (x^2)^2 - (3y^2)^2 = (x^2 - 3y^2)(x^2 + 3y^2) $

13) $ (x - 1)(x + 1) = x^2 - 1^2 = x^2 - 1 $

14) $ (x - 5)(x + 5) = x^2 - 5^2 = x^2 - 25 $

15) $ (x - 6)(6 + x) = (x - 6)(x + 6) = x^2 - 6^2 = x^2 - 36 $

16) $ (2x + 1)(2x - 1) = (2x)^2 - 1^2 = 4x^2 - 1 $

17) $ (x - 2y)(2y + x) = (x - 2y)(x + 2y) = x^2 - (2y)^2 = x^2 - 4y^2 $

18) $ (5x - 3y)(3y + 5x) = (5x - 3y)(5x + 3y) = (5x)^2 - (3y)^2 = 25x^2 - 9y^2 $

19) $ (\frac{1}{x} - 5)(\frac{1}{x} + 5) = (\frac{1}{x})^2 - 5^2 = \frac{1}{x^2} - 25 $

20) $ (x - \frac{3}{2})(x + \frac{3}{2}) = x^2 - (\frac{3}{2})^2 = x^2 - \frac{9}{4} $

21) $ (\frac{x}{3} - \frac{y}{4})(\frac{x}{3} + \frac{y}{4}) = (\frac{x}{3})^2 - (\frac{y}{4})^2 = \frac{x^2}{9} - \frac{y^2}{16} $

22) $ (\frac{x}{y} - \frac{2}{3})(\frac{x}{y} + \frac{2}{3}) = (\frac{x}{y})^2 - (\frac{2}{3})^2 = \frac{x^2}{y^2} - \frac{4}{9} $

23) $ (\frac{x}{2} + \frac{y}{3})(\frac{y}{3} - \frac{x}{2}) = (\frac{y}{3} + \frac{x}{2})(\frac{y}{3} - \frac{x}{2}) = (\frac{y}{3})^2 - (\frac{x}{2})^2 = \frac{y^2}{9} - \frac{x^2}{4} $

24) $ (2x - \frac{2}{3})(\frac{2}{3} + 2x) = (2x - \frac{2}{3})(2x + \frac{2}{3}) = (2x)^2 - (\frac{2}{3})^2 = 4x^2 - \frac{4}{9} $