Câu 1:(X/2+2y^2)(x/2-2y^2) Câu 2:(1/2x-4y)^2 Câu3: (x^2-4). (x^2+4) Câu 4:(x +y)^2 +(x-y)^2 Câu 5:(2x+3)^2 -(x+1)^2 08/08/2021 Bởi Sadie Câu 1:(X/2+2y^2)(x/2-2y^2) Câu 2:(1/2x-4y)^2 Câu3: (x^2-4). (x^2+4) Câu 4:(x +y)^2 +(x-y)^2 Câu 5:(2x+3)^2 -(x+1)^2
Đáp án: Giải thích các bước giải: $Câu1:_{}$ $(\frac{x}{2}+2y^2)(\frac{x}{2}-2y^2)_{}$ ⇔ $(\frac{x}{2})^2-(2y^2)^2_{}$ ⇔ $\frac{x^2}{4}-4y^4_{}$ $Câu2:_{}$ $(\frac{1}{2}-4y)^2_{}$ ⇔ $(\frac{1}{2})^2.\frac{1}{2}.4y+(4y)^2_{}$ ⇔ $\frac{1}{4}x^2-4xy+16y^2_{}$ $Câu3:_{}$ $(x^2-4)(x^2+4)_{}$ ⇔ $(x^2)^2-4^2_{}$ ⇔ $x^4-16_{}$ $Câu4:_{}$ $(x+y)^2+(x-y)^2_{}$ ⇔ $x^2+2xy+y^2+x^2-2xy+y^2_{}$ ⇔ $2x^2+2y^2_{}$ $Câu5:_{}$ $(2x+3)^2-(x+1)^2_{}$ ⇔ $[2x+3-(x+1) ].[2x+3+(x+1) ]_{}$ ⇔ $(2x+3-x-1)(2x+3+x+1)_{}$ ⇔ $(x+2)(3x+4)_{}$ Bình luận
1. `(x/2 + 2y^2)(x/2 – 2y^2) = (x/2)^2 – (2y^2)^2 = (x^2)/4 – 4y^4` 2. `(1/2 x-4y)^2 = (1/2 x)^2 – 2. 1/2 x.4y + (4y)^2 = 1/4 x^2 – 4xy + 16y^2` 3. `(x^2-4).(x^2+4) = (x^2)^2 – 4^2 = x^4-16` 4. `(x+y)^2 + (x-y)^2 = x^2+2xy+y^2 + x^2-2xy +y^2 = 2x^2+2y^2` 5. `(2x+3)^2 – (x+1)^2 = (2x+3+x+1)(2x+3-x-1) = (3x+4)(x+2)` Bình luận
Đáp án:
Giải thích các bước giải:
$Câu1:_{}$ $(\frac{x}{2}+2y^2)(\frac{x}{2}-2y^2)_{}$
⇔ $(\frac{x}{2})^2-(2y^2)^2_{}$
⇔ $\frac{x^2}{4}-4y^4_{}$
$Câu2:_{}$ $(\frac{1}{2}-4y)^2_{}$
⇔ $(\frac{1}{2})^2.\frac{1}{2}.4y+(4y)^2_{}$
⇔ $\frac{1}{4}x^2-4xy+16y^2_{}$
$Câu3:_{}$ $(x^2-4)(x^2+4)_{}$
⇔ $(x^2)^2-4^2_{}$
⇔ $x^4-16_{}$
$Câu4:_{}$ $(x+y)^2+(x-y)^2_{}$
⇔ $x^2+2xy+y^2+x^2-2xy+y^2_{}$
⇔ $2x^2+2y^2_{}$
$Câu5:_{}$ $(2x+3)^2-(x+1)^2_{}$
⇔ $[2x+3-(x+1) ].[2x+3+(x+1) ]_{}$
⇔ $(2x+3-x-1)(2x+3+x+1)_{}$
⇔ $(x+2)(3x+4)_{}$
1. `(x/2 + 2y^2)(x/2 – 2y^2) = (x/2)^2 – (2y^2)^2 = (x^2)/4 – 4y^4`
2. `(1/2 x-4y)^2 = (1/2 x)^2 – 2. 1/2 x.4y + (4y)^2 = 1/4 x^2 – 4xy + 16y^2`
3. `(x^2-4).(x^2+4) = (x^2)^2 – 4^2 = x^4-16`
4. `(x+y)^2 + (x-y)^2 = x^2+2xy+y^2 + x^2-2xy +y^2 = 2x^2+2y^2`
5. `(2x+3)^2 – (x+1)^2 = (2x+3+x+1)(2x+3-x-1) = (3x+4)(x+2)`