45^3.20^4.18^2/1805
45^3.20^4.18^2/180^5
45^3.20^4.18^2/180^5
tính :
\(\frac{45^3.20^4.18^2}{180^5}\)
ta có tử =453x204x182=45x45x45x20x20x20x20x18x18
=45x45x45x4x5x4x5x4x5x4x5x18x18
=(45x4x45x4x45x4)x4x5x5x5x5x18x18
=(180x180x180)x4x5x5x5x5x9x2x9x2
=(180x180x180)x(4x5x9x2x2x5x9)x5x5
=(180x180x180x180x180)x25
=1805x25
lại có:180mũ5x25:180mux5=25
H= 45^3.20^4.18^2/ 180^5 = (3^2.5)^3.(2^2.5)^4.(2.3^2)^2/ (2^2.3^2.5)^5 = 3^6.5^3.2^8.5^4.2^2.3^4/ 2^10.3^10.5^5 = 3^10.5^7.2^10/ 2^10.3^10.5^5 = 5^2=25
Tính giá trị của các biểu thức:
G=21^2.14.125/35^5.6
H= 45^3.20^4.18^2/180^5
HELP ME
G=(212.14.125):355.6
=\(\frac{\left(3.7\right)^2.7.2.5^{^3}}{\left(7.5\right)^5.2.3}\)=\(\frac{3^2.7^2.7.5^3}{7^5.5^5.3}\)=\(\frac{3}{7^2.5^2}\)=\(\frac{3}{49.25}\)=\(\frac{3}{1225}\)
\(G=\frac{21^2.14.125}{35^5.6}\)
\(G=\frac{\left(3.7\right)^2.7.2.5^3}{\left(7.5\right)^5.2.3}=\frac{3}{7^2.5^2}=\frac{3}{49.25}=\frac{3}{1225}\)
rút gọn phân số
a)\(\dfrac{4^6.3^4.9^5}{6^{12}}\)
b)\(\dfrac{21^2.14.125}{35^2.6}\)
c)\(\dfrac{45^3.20^4.18^2}{180^5}\)
d)\(\dfrac{2^{13}+2^5}{2^{10}+2^2}\)
a: \(=\dfrac{2^{12}\cdot3^{14}}{3^{12}\cdot2^{12}}=3^2=9\)
b: \(=\dfrac{7^3\cdot2\cdot5^3}{5^2\cdot7^2\cdot6}=7\cdot5\cdot\dfrac{1}{3}=\dfrac{35}{3}\)
d: =2^5(2^8+1)/2^2(2^8+1)=2^3=8
c: \(=\dfrac{5^3\cdot3^6\cdot2^8\cdot5^4\cdot3^4\cdot2^2}{2^{10}\cdot3^{10}\cdot5^5}=5^2\)
Tính giá trị biểu thức :
C = \(\frac{21^2.14.125}{35^3.6}\)
D = \(\frac{45^3.20^4.18^2}{180^5}\)
\(C=\frac{21^2.14.125}{35^3.6}\)
\(C=\frac{\left(3.7\right)^2.2.7.5^3}{\left(5.7\right)^3.2.3}\)
\(C=\frac{3^2.7^2.2.7.5^3}{5^3.7^3.2.3}\)
\(C=\frac{3^2.7^3.2.5^3}{5^3.7^3.2.3}=3\)
\(D=\frac{45^3.20^4.18^2}{180^5}\)
\(D=\frac{\left(5.3^2\right)^3.\left(2^2.5\right)^4.\left(2.3^2\right)^2}{\left(2^2.3^2.5\right)^5}\)
\(D=\frac{5^3.3^6.2^8.5^4.2^2.3^4}{2^{10}.3^{10}.5^5}\)
\(D=\frac{5^7.3^{10}.2^{10}}{2^{10}.3^{10}.5^5}=5^2=25\)
1)\(\frac{21^2.14.125}{35^2.6}\)
2)\(\frac{45^3.20^4.18^2}{180^5}\)
AI TRA LOI DUOC MK TICK CHO !!! CAM ON !!!
\(\frac{21^2\cdot14\cdot125}{35^2\cdot6}=\frac{3^2\cdot7^2\cdot2\cdot25\cdot3}{5^2\cdot7^2\cdot2\cdot3}=\frac{3^4\cdot7^2\cdot2\cdot5^2}{5^2\cdot7^2\cdot2\cdot3}=3^3=27..\)
\(\frac{45^3\cdot20^4\cdot18^2}{180^5}=\frac{5^3\cdot9^3\cdot4^4\cdot5^4\cdot2^2\cdot9^2}{2^{10}\cdot3^{10}\cdot5^5}=\frac{5^7\cdot9^5\cdot4^4}{4^5\cdot9^5\cdot5^5}=\frac{1}{4}=0.25\)
Cho mk hỏi thêm D=\(\dfrac{21^2.14.125}{35^3.6}\); E= \(\dfrac{45^3.20^4.18^2}{180^5}\)và F= \(\dfrac{2^{13}+2^5}{2^{10}+2^2}\)nhé. Cảm ơn mọi người rất nhiều. Tại mk học thêm mà mk thấy khó quá nên hỏi:))
d) Ta có: \(D=\dfrac{21^2\cdot14\cdot125}{35^3\cdot6}\)
\(=\dfrac{7^2\cdot3^2\cdot7\cdot2\cdot5^3}{5^3\cdot7^3\cdot6}\)
\(=\dfrac{3^2\cdot2}{6}=\dfrac{6\cdot3}{6}=3\)
e) Ta có: \(E=\dfrac{45^3\cdot20^4\cdot18^2}{180^5}\)
\(=\dfrac{3^6\cdot5^3\cdot2^8\cdot5^4\cdot3^4\cdot2^2}{2^{10}\cdot3^{10}\cdot5^5}\)
\(=\dfrac{3^{10}\cdot5^7\cdot2^{10}}{2^{10}\cdot3^{10}\cdot5^5}=25\)
f) Ta có: \(F=\dfrac{2^{13}+2^5}{2^{10}+2^2}\)
\(=\dfrac{2^5\left(2^8+1\right)}{2^2\left(2^8+1\right)}=\dfrac{2^5}{2^2}=\dfrac{32}{4}=8\)
Giải:
\(D=\dfrac{21^2.14.125}{35^3.6}\)
\(D=\dfrac{\left(3.7\right)^2.\left(2.7\right).5^3}{\left(5.7\right)^3.\left(2.3\right)}\)
\(D=\dfrac{3^2.7^2.2.7.5^3}{5^3.7^3.2.3}\)
\(D=\dfrac{3^2.7^3.2.5^3}{5^3.7^3.2.3}\)
\(D=3\)
\(E=\dfrac{45^3.20^4.18^2}{180^5}\)
\(E=\dfrac{\left(3^2.5\right)^3.\left(2^2.5\right)^4.\left(2.3^2\right)^2}{\left(2^2.3^2.5\right)^5}\)
\(E=\dfrac{\left(3^2\right)^3.5^3.\left(2^2\right)^4.5^4.2^2.\left(3^2\right)^2}{\left(2^2\right)^5.\left(3^2\right)^5.5^5}\)
\(E=\dfrac{3^6.5^7.2^8.2^2.3^4}{2^{10}.3^{10}.5^5}\)
\(E=\dfrac{3^{10}.5^7.2^{10}}{2^{10}.3^{10}.5^5}\)
\(E=5^2=25\)
\(F=\dfrac{2^{13}+2^5}{2^{10}+2^2}\)
\(F=\dfrac{2^2.2^3.2^8+2^2.2^3}{2^2.2^8+2^2}\)
\(F=\dfrac{2^2.2^3\left(2^8+1\right)}{2^2.\left(2^8+1\right)}\)
\(F=2^3=8\)
Bài này lúc đầu mk cx ko thành thạo về bài này nên mk thấy khó nhưng sau đó mk luyện bài này nên đã lm quên vs bài này rồi!
Mk gợi ý lm bài này nha:
Nếu là nhân hay chia mk phải phân tích ra thừa số
Nếu là cộng hay trừ mk phải tách ra sao cho nó có thể tính nhanh
Đấy là cách lm của mk!
rút gọn
A = 72^3.5^42/108^4
B= 45^3.20^4.18^2/180^5
C= 11.3^22.3^7-9^15/(2.3^14)^2
A = \(\dfrac{72^3.5^{42}}{108^4}\)
= \(\dfrac{\left(2^3.3^2\right)^3.5^{42}}{\left(2^2.3^3\right)^4}\)
= \(\dfrac{2^9.3^6.5^{42}}{2^8.3^{12}}\)
= \(\dfrac{2.5^{42}}{3^6}\)
@trần phúc nguyên
B = \(\dfrac{45^3.20^4.18^2}{180^5}\)
= \(\dfrac{\left(3^2.5\right)^3\left(2^2.5\right)^4.\left(2.3^2\right)^2}{\left(2^2.3^2.5\right)^5}\)
= \(\dfrac{3^6.5^3.2^8.5^4.2^2.3^4}{2^{10}.3^{10}.5^5}\)
= \(\dfrac{3^{10}.5^7.2^{10}}{2^{10}.3^{10}.5^5}\)
= 25
@trần phúc nguyên
C = \(\dfrac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}\)
= \(\dfrac{11.3^{29}-\left(3^2\right)^{15}}{2^2.3^{28}}\)
= \(\dfrac{11.3^{29}-3^{30}}{2^2.3^{28}}\)
= \(\dfrac{3^{29}\left(11-3\right)}{2^2.3^{28}}\)
= \(\dfrac{33-9}{4}\)
= 6
@trần phúc nguyên
Tìm giá trị biểu thức:
a) A=\(\dfrac{45^3.20^4.18^2}{180^5}\)
b) B=\(\dfrac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}\)
453 = (9.5)3 = 36.53
204 = (4.5)4 = 28.54
182 = (9.2)2 = 34.22
1805 = (4.9.5)5 = 210.310.55
\(=\dfrac{3^6.5^3.2^8.5^4.3^4.2^2}{2^{10}.3^{10}.5^5}=\dfrac{2^{10}.3^{10}.5^7}{2^{10}.3^{10}.5^5}=5^2=25\)
\(B=\dfrac{11.3^{29}-3^{30}}{4.3^{28}}=\dfrac{3^{29}\left(11-3\right)}{3^{28}.4}=\dfrac{3.8}{4}=6\)