RÚT GỌN BIỂU THỨC SAU
3(22+1)(24+1)(28+1)(216+1)(232+1)(264+1)
\(3\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^{16}-1\right)\left(2^{16}+1\right)\)
\(=2^{32}-1\)
1,rút gọn biểu thức: (2+1)(22+1)(24+1)(28+1)(216+1)
2,tìm x, biết: x2-6x=-9
1,
Đặt \(A=\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(\left(2-1\right)A=\left(2-1\right)\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(1A=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(A=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(A=\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(A=\left(2^{16}-1\right)\left(2^{16}+1\right)\)
\(A=2^{32}-1\)
Vậy \(A=2^{32}-1\)
2, \(x^2-6x=-9\)
\(x^2-6x+9=0\)
\(\left(x-3\right)^2=0\)
\(x-3=0\)
\(x=3\)
Vậy \(x=3\)
bài 5 : rút gọn các biểu thức sau:
A=1002-992+982-972+....+22-12
B=3(22+1)(24+1)(28+1)....(264+1)+1
C=(a+b+c)2+(a+b-c)2-2(a+b)2
CẦN GẤP!!!!!
Rút gọn biểu thức
3(22+1)(24+1)(28+1)(216+1)
Cảm ơn mn nhiều
\(A=3\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^{16}-1\right)\left(2^{16}+1\right)\)
\(=2^{32}-1\)
Đặt : \(P=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^{16}-1\right)\left(2^{16}+1\right)\)
\(=2^{32}-1\)
3(22+1)(24+1)(28+1)(216+1
=\(\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
=\(\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
=\(\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
=\(\left(2^{16}-1\right)\left(2^{16}+1\right)\)
=\(2^{32}-1\)
Bài 3: Rút gọn biểu thức:
a) (6x+1)2+(6x-1)2-2(1+6x)(6x-1); b) 3(22+1)(24+1)(28+1)(216+1); c) x(2x2-3)-x2(5x+1)+x2; d) 3x(x-2)-5x(1-x)-8(x2-3)
Câu 21: So sánh M = 232 và N = (2 + 1)(22 + 1)(24 + 1)(28 + 1)(216 + 1)
A. M > N B. M < N C. M = N D. M = N – 1
Câu 22: Tìm giá trị lớn nhất của biểu thức B = 4 – 16x2 – 8x
A. 5 B. -5 C. 8 D.-8
Câu 23: Biểu thức E = x2 – 20x +101 đạt giá trị nhỏ nhất khi
A. x = 9 B. x = 10 C. x = 11 D.x = 12
Câu 24: Kết quả của phép chia 15x3y4 : 5x2y2 là
A. 3xy2 B. -3x2y C. 5xy D. 15xy2
Câu 25: Kết quả của phép chia (6xy2 + 4x2y – 2x3) : 2x là
A. 3y2 + 2xy – x2 B. 3y2 + 2xy + x2 C. 3y2 – 2xy – x2 D. 3y2 + 2xy
Câu 21: So sánh M = 232 và N = (2 + 1)(22 + 1)(24 + 1)(28 + 1)(216 + 1)
A. M > N B. M < N C. M = N D. M = N – 1
Câu 22: Tìm giá trị lớn nhất của biểu thức B = 4 – 16x2 – 8x
A. 5 B. -5 C. 8 D.-8
Câu 23: Biểu thức E = x2 – 20x +101 đạt giá trị nhỏ nhất khi
A. x = 9 B. x = 10 C. x = 11 D.x = 12
Câu 24: Kết quả của phép chia 15x3y4 : 5x2y2 là
A. 3xy2 B. -3x2y C. 5xy D. 15xy2
Câu 25: Kết quả của phép chia (6xy2 + 4x2y – 2x3) : 2x là
A. 3y2 + 2xy – x2 B. 3y2 + 2xy + x2 C. 3y2 – 2xy – x2 D. 3y2 + 2xy
1. Rút gọn các biểu thức sau:
A = 1002- 992 + 982 - 972 + ... + 22 - 12
B = 3(22+ 1) (24 + 1) ... (264 + 1) + 1
C = (a + b + c)2+ (a + b - c)2 - 2(a + b)2
(a) (2 + 1)(22 + 1)(24 + 1)(28 + 1)(216 + 1) = 232 − 1
a) Ta có: \(\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2-1\right)\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)
\(=\left(2^{16}-1\right)\left(2^{16}+1\right)\)
\(=2^{32}-1\)
1. Rút gọn các biểu thức sau:
a. A = 1002 - 992+ 982 - 972 + ... + 22 - 12
b. B = 3(22 + 1) (24 + 1) ... (264 + 1) + 12
c. C = (a + b + c)2 + (a + b - c)2 - 2(a + b)2
a: \(A=\left(100-99\right)\left(100+99\right)+\left(98+97\right)\left(98-97\right)+....+\left(2+1\right)\left(2-1\right)\)
\(=100+99+98+97+...+2+1\)
=5050
b: \(B=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\cdot...\cdot\left(2^{64}+1\right)+1\)
\(=\left(2^4-1\right)\left(2^4+1\right)\cdot...\cdot\left(2^{64}+1\right)+1\)
\(=\left(2^8-1\right)\left(2^8+1\right)\cdot...\cdot\left(2^{64}+1\right)+1\)
\(=\left(2^{16}-1\right)\left(2^{16}+1\right)\left(2^{32}+1\right)\left(2^{64}+1\right)+1\)
\(=\left(2^{32}-1\right)\left(2^{32}+1\right)\left(2^{64}+1\right)+1\)
\(=\left(2^{64}-1\right)\cdot\left(2^{64}+1\right)+1\)
\(=2^{128}-1+1=2^{128}\)
a. \(A=100^2-99^2+98^2-97^2+...+2^2-1^2\)
\(=\left(100-99\right)\left(100+99\right)+\left(98-97\right)\left(98+97\right)+...+\left(2-1\right)\left(2+1\right)\)
\(=199+195+...+3\)
\(=\dfrac{\left(199+3\right)\left(\dfrac{199-3}{4}+1\right)}{2}=5050\)
b. \(B=3\left(2^2+1\right)\left(2^4+1\right)...\left(2^{64}+1\right)+1^2\)
\(=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)...\left(2^{64}+1\right)+1^2\)
\(=\left(2^4-1\right)\left(2^4+1\right)...\left(2^{64}+1\right)+1^2\)
\(=2^{128}-1+1=2^{128}\)
c) \(C=\left(a+b+c\right)^2+\left(a+b-c\right)^2-2\left(a+b\right)^2\)
\(=a^2+b^2+c^2+2ab+2ac+2bc+a^2+b^2+c^2+2ab-2ac-2bc-2a^2-2b^2-4ab\)
\(=2c^2\)
Rút gọn các biểu thức sau:
a. A = 1002 - 992+ 982 - 972 + ... + 22 - 12
b. B = 3(22 + 1) (24 + 1) ... (264 + 1) + 12
c. C = (a + b + c)2 + (a + b - c)2 - 2(a + b)2
\(A=\left(100-99\right)\left(100+99\right)+\left(99-98\right)\left(98+97\right)+...+\left(2-1\right)\left(2+1\right)\\ A=100+99+99+98+...+2+1\\ A=\left(100+1\right)\left(100-1+1\right):2=5050\)
\(B=\left(2-1\right)\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)...\left(2^{64}+1\right)+1\\ B=\left(2^1-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)...\left(2^{64}+1\right)+1\\ B=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)...\left(2^{64}+1\right)+1\\ B=\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)...\left(2^{64}+1\right)+1\\ B=\left(2^{16}-1\right)\left(2^{16}+1\right)\left(2^{32}+1\right)\left(2^{64}+1\right)+1\\ B=\left(2^{32}-1\right)\left(2^{32}+1\right)\left(2^{64}+1\right)+1\\ B=\left(2^{64}-1\right)\left(2^{64}+1\right)+1=2^{128}-1+1=2^{128}\)
\(C=a^2+b^2+c^2+2ab+2bc+2ac+a^2+b^2+c^2+2ab-2ac-2bc-2a^2-4ab-2b^2\\ C=2c^2\)