Question

Bài 1:Tính:

a)(1/27.x^3-y^3)

b)(2x^2-3y^3)

bài 2:Rút gọn biểu thức:

a)(6x+1)^2+(6x-1)^2-2.(1+6x).(1+6x)

b)3(2^2+1).(2^2-1).(2^8+1).(2^16+1)

c)C=12(5^2+1).(5^4+1).(5^8+1).(5^16+1)

giúp mk vx, mk cần gấp...T^T

Answer 1

Bài 1 không có cơ sở để tính biểu thức.

Answer 2

Bài 2:

a. 

$(6x+1)^2+(6x-1)^2-2(6x+1)(6x-1)$

$=[(6x+1)-(6x-1)]^2=2^2=4$

b.

$3(2^2+1)(2^4+1)(2^8+1)(2^{16}+1)$

$=(2^2-1)(2^2+1)(2^4+1)(2^8+1)(2^{16}+1)$

$=(2^4-1)(2^4+1)(2^8+1)(2^{16}+1)$

$=(2^8-1)(2^8+1)(2^{16}+1)$
$=(2^{16}-1)(2^{16}+1)=2^{32}-1$

c.

$2C=(5^2-1)(5^2+1)(5^4+1)(5^8+1)(5^{16}+1)$

$=(5^4-1)(5^4+1)(5^8+1)(5^{16}+1)$

$=(5^8-1)(5^8+1)(5^{16}+1)$
$=(5^{16}-1)(5^{16}+1)=5^{32}-1$

$\Rightarrow C=\frac{5^{32}-1}{2}$