Bài 8:

a) \(2^{225}=\left(2^3\right)^{75}=8^{75}\)

\(3^{150}=\left(3^2\right)^{75}=9^{75}\)

Vì \(8^{75}< 9^{75}\Rightarrow2^{225}< 3^{150}\)

b) \(2^{91}=\left(2^{13}\right)^7=8192^7\)

\(5^{35}=\left(5^5\right)^7=3125^7\)

Vì \(8192^7>3125^7\Rightarrow2^{91}>5^{35}\)

c) \(99^{20}=\left(99^2\right)^{10}=9801^{10}< 9999^{10}\)

a: \(45^{10}\cdot5^{30}=45^{10}\cdot\left(5^3\right)^{10}\)

\(=\left(45\cdot5^3\right)^{10}=\left(3^2\cdot5^4\right)^{10}=3^{20}\cdot5^{40}\)

\(75^{19}=\left(5^2\cdot3\right)^{19}=5^{38}\cdot3^{19}\)

\(\frac{45^{10}\cdot5^{30}}{75^{19}}=\frac{3^{20}\cdot5^{40}}{5^{38}\cdot3^{19}}=5^2\cdot3=75>1\)

Do đó: \(45^{10}\cdot5^{30}>75^{19}\)

=>Đúng

b: Đúng

c: \(99^{20}=\left(99^2\right)^{10}=9801^{10}<9999^{10}\)

=>Sai

7520 = 4510.530

Ta có: 4510.530 = (9.5)10.530 = 910.510.530 = (32)10.540

=320.(52)20 = 320.2520 = (3.25)20 = 7520

Vế phải bằng vế trái nên đẳng thức được chứng minh

128.912 = 1816

Ta có: 128.912 = (4.3)8.912 =48.38.912 =(22)8.(32)4.912

= 216.94.912 = 216.916= (2.9)16 = 1816

Vế trái bằng vế phải nên đẳng thức được chứng minh

Tính nhanh

1001 * 789 + 456 * 128 + 912 * 436 

1001 . 789 + 456 . 128 + 912 .436 = 1245789

k nha

Tìm y biết

16/3+0,357×(y-5/3)=3/4:9/4+5

bạn hỏi để câu L-I-K-E ak

27549 + 7520 = 35069

k mk mk k lại

de khong phai la : 27549+7520+=dau ma phai la : 27549+7520=moi dung em viet thuc dau cong roi 

27549+7520=35069

chuc em thanh cong trong hoc tap 

good luck to you !

\(11\div\left\{\frac{7}{8}-3\cdot\left[0,25\div\left(1\frac{1}{3}+2\cdot\frac{1}{3}\right)\right]\right\}\)

\(=11\div\left\{\frac{7}{8}-3\cdot\left[\frac{1}{4}\div\left(\frac{4}{3}+2\cdot\frac{1}{3}\right)\right]\right\}\)

\(=11\div\left\{\frac{7}{8}-3\cdot\left[\frac{1}{4}\div\left(\frac{4}{3}+\frac{2}{3}\right)\right]\right\}\)

\(=11\div\left\{\frac{7}{8}-3\cdot\left[\frac{1}{4}\div2\right]\right\}\)

\(=11\div\left\{\frac{7}{8}-3\cdot\frac{1}{8}\right\}\)

\(=11\div\left\{\frac{7}{8}-\frac{3}{8}\right\}\)

\(=11\div\frac{1}{2}\)

\(=22\)

b) 101*789 + 456*128 - 789 + 912*436

= 789*100 + 456*128 + 912*436

= 789*100 + 912*64 + 912*436

= 789*100 + 912*500

= 100*(789 + 912*5)

= 100*5349

= 534900

C

C

TL

\(\frac{7520}{6400} > \frac{70}{196}

nha bn

HT

7520/6400>70/196