Lời giải:
$A=(9+1)(9^2+1)(9^4+1)(9^8+1)$
$8A=(9-1)(9+1)(9^2+1)(9^4+1)(9^8+1)$
$=(9^2-1)(9^2+1)(9^4+1)(9^8+1)$
$=(9^4-1)(9^4+1)(9^8+1)$
$=(9^8-1)(9^8+1)=9^{16}-1$
$\Rightarrow A=\frac{9^{16}-1}{8}$
Bài 3: Những hằng đẳng thức đáng nhớ
Các câu hỏi tương tự
Giúp mình với mình đang cần gấp.
Rút Gọn:
\(^{\left(x^4-3x^2+9\right)\left(x^2+3\right)-\left(3+x^2\right)^2}\)
\(\left(x^2-1\right)^3-\left(x^4+x^2+1\right)\left(x^2-1\right)\)
\(5\left(x+2\right)\left(x-2\right)-\left(3-4x\right)^2+17\)
H24
20 tháng 1 2022 lúc 20:54
Tính tích: A=\(\left(1-\dfrac{1}{4}\right)\left(1-\dfrac{1}{9}\right)...\left(1-\dfrac{1}{10000}\right)\)
Rút gọn các biểu thức:
\(A=\left(5a+5\right)^2+10\left(a-3\right)\left(1+a\right)+a^2-6a+9\)
B = \(\left(6a-2\right)^2+4\left(3a-1\right)\left(1-2b\right)\left(2b-1\right)^2\)
Tìm x:
1,left(3x-5right)^2-left(3x+1right)^28
2,2x.left(8x-3right)-left(4x-3right)^227
3,left(2x-3right)^2-left(2x+1right)^23
4, left(x+5right)^2-x^245
5, left(x-3right)^3-left(x-3right).left(x^2+3x+9right)+9.left(x+1right)^218
6,x.left(x-4right).left(x+4right)-left(x-5right).left(x^2+5x+25right)13
Đọc tiếp
Tìm x:
\(1,\left(3x-5\right)^2-\left(3x+1\right)^2=8\)
2,\(2x.\left(8x-3\right)-\left(4x-3\right)^2=27\)
3,\(\left(2x-3\right)^2-\left(2x+1\right)^2=3\)
4, \(\left(x+5\right)^2-x^2=45\)
5, \(\left(x-3\right)^3-\left(x-3\right).\left(x^2+3x+9\right)+9.\left(x+1\right)^2=18\)
6,\(x.\left(x-4\right).\left(x+4\right)-\left(x-5\right).\left(x^2+5x+25\right)=13\)
Tính
a/ left(x-3right)left(x^2+3x+9right)
b/ left(x-2right)left(x^2+2x+4right)
c/ left(x+4right)left(x^2-4x+16right)
d/ left(x-3yright)left(x^2+3xy+9y^2right)
e/ left(x^2-frac{1}{3}right)left(x^4+frac{1}{3}x^2+frac{1}{9}right)
f/ left(frac{1}{3}x+2yright)left(frac{1}{9}x^2-frac{2}{3}xy+4y^2right)
Đọc tiếp
Tính
a/ \(\left(x-3\right)\left(x^2+3x+9\right)\)
b/ \(\left(x-2\right)\left(x^2+2x+4\right)\)
c/ \(\left(x+4\right)\left(x^2-4x+16\right)\)
d/ \(\left(x-3y\right)\left(x^2+3xy+9y^2\right)\)
e/ \(\left(x^2-\frac{1}{3}\right)\left(x^4+\frac{1}{3}x^2+\frac{1}{9}\right)\)
f/ \(\left(\frac{1}{3}x+2y\right)\left(\frac{1}{9}x^2-\frac{2}{3}xy+4y^2\right)\)
1. Rút gọn các biểu thức sau:
a) \(\left(x+y\right)^2-\left(x-y\right)^2\)
b) \(\left(a+b\right)^3+\left(a-b\right)^3-2a^3\)
c) \(9^8\times2^8-\left(18^4-1\right)\left(18^4+1\right)\)
Tìm x:
a/ \(\left(6x-2\right)^2+\left(5x-2\right)^2-4\left(3x-1\right)\left(5x-2\right)=0\)
b/ \(\left(x-1\right)\left(x^2+x+1\right)-x\left(x+2\right)\left(x-2\right)=5\)
c/ \(\left(x-1\right)^3-\left(x+3\right)\left(x^2-3x+9\right)+3\left(x^2-4\right)=2\)
1) \(27+\left(x-3\right).\left(x^2+3x+9\right)=-x\)
2) \(-4\left(x+2\right)-7\left(2x-1\right)+9\left(4-3x\right)=30\)
3) \(x^2-4x+4=0\)
4) \(\left(x-1\right).\left(x^2+x+1\right)-x.\left(x+2\right).\left(x-2\right)=5\)
Tìm x giúp mk vs nha mai mk đi hk rùi
tìm x biết
a)\(\left(x-2\right)^2-x\left(x+1\right)\left(x-1\right)+6x\left(x-3\right)=0\)
b)\(\left(x-2\right)\left(x^2-2x+4\right)\left(x+2\right)\left(x^2+2x+4\right)-x^6+2x=1\)
c)\(\left(x-3\right)\left(x^2+3x+9\right)+x\left(x+2\right)\left(2-x\right)=1\)