GIẢI RA THÌ HƠI DÀI NHG KO SEO, MK WILL CỐ GẮNG ^_^

= ( 16³ . 2⁵ : 2⁴⁰ ) . ( 9⁴ . 27⁵ . 81 . 3¹² . 9²⁴ : 27¹⁸ ) . ( 125⁵ . 25² ) ( Chỗ nài nhiều số quá ko bt mk có bỏ sót ko )

= ( 2¹² . 2⁵ : 2⁴⁰ ) . ( 3⁸ . 3¹⁵ . 3⁴ . 3¹² . 3⁴⁸ : 3⁵⁴ ) . ( 5¹⁵ . 5⁴ )

= 2^{12 + 5 - 40} . 3^{8 + 15 + 4 + 12 + 48 - 54} . 5^{15 + 4}

= 2^-23 . 3³³ . 5¹⁹

Đó, chắc sai r bn đừng chép vào, nhiều số đâm ra mk hay bj lú

Bn tk mk ik, mk mất tận 20' để giải đó

a: =5*1,4-4*1,5+3*1,3

=7-6+3,9=4,9

b: =1/3*7+3/4*18-2/3*20

=7/3+54/4-40/3

=-11+54/4

=2,5

c: =5/6*17-1/2*16+2/5*15

=85/6-8+6

=85/6-2

=73/6

d: =15*4/5+12*3/4-18*4/9

=12+9-8

=12+1=13

Sai ở chỗ:<=> 4-9/2 = 5-9/2 <=> 4=5

thế này mới đúng!

 \(\left(4-\frac{9}{2}\right)^2=\left(5-\frac{9}{2}\right)^2\Leftrightarrow\left(4-\frac{9}{2}\right)\left(4-\frac{9}{2}\right)=\left(5-\frac{9}{2}\right)\left(5-\frac{9}{2}\right)\)

a,

\(\sqrt{0,0004}=0.02\)

\(\sqrt{\frac{16}{81}}=\frac{\sqrt{16}}{\sqrt{81}}=\frac{4}{9}\)

\(\sqrt{25}=5\)

\(\sqrt{0,16}=0,4\)

b,\(\sqrt{\frac{9}{16}}+\sqrt{\frac{25}{9}}\)

= \(\frac{\sqrt{9}}{\sqrt{16}}+\frac{\sqrt{25}}{\sqrt{9}}\)

= \(\frac{3}{4}+\frac{5}{3}\)

=\(\frac{29}{12}\)

bấm máy tính đi bạn, nhanh hơn

ĐÂY LÀ TÍNH NHANH

theo đề bài ra ta có:1+4+9+16+25+36+49+64+81+100

=(1+49)+(4+16)+(9+81)+(36+64)+(25+100)

=50+20+100+100+125

=70+100+100+125

=170+100+125

=270+125

=395

a: \(\dfrac{\sqrt{81}}{\sqrt{16}}=\dfrac{9}{4}=\dfrac{36}{16}< \dfrac{81}{16}\)

b: \(\sqrt{16+25}=\sqrt{41}< 9=\sqrt{16}+\sqrt{25}\)

a) \(\sqrt{\frac{25}{81}\cdot\frac{16}{49}\cdot\frac{169}{9}}\\ =\sqrt{\left(\frac{5}{9}\right)^2\cdot\left(\frac{4}{7}\right)^2\cdot\left(\frac{13}{3}\right)^2}\\ =\sqrt{\left(\frac{5}{9}\cdot\frac{4}{7}\cdot\frac{13}{3}\right)^2}\\ =\frac{5}{9}\cdot\frac{4}{7}\cdot\frac{13}{3}\\ =\frac{260}{189}\)

b) \(\sqrt{3\frac{1}{6}\cdot2\frac{14}{25}\cdot2\frac{34}{81}}\\ =\sqrt{\frac{19}{6}\cdot\frac{64}{25}\cdot\frac{196}{81}}\\ =\sqrt{\frac{19}{6}\cdot\left(\frac{8}{5}\right)^2\cdot\left(\frac{14}{9}\right)^2}\\ =\sqrt{\frac{19}{6}\cdot\left(\frac{8}{5}\cdot\frac{14}{9}\right)^2}\\ =\sqrt{\frac{19}{6}\cdot\frac{112}{45}}\\ =\sqrt{\frac{1064}{135}}\)

Bổ sung câu b :

\(\sqrt{3\frac{1}{16}.2\frac{14}{25}.2\frac{34}{81}}=\sqrt{\frac{49}{16}.\frac{64}{25}.\frac{196}{81}}=\sqrt{\frac{49}{16}}.\sqrt{\frac{64}{25}}.\sqrt{\frac{196}{81}}=\frac{7}{4}.\frac{8}{5}.\frac{14}{9}=\frac{196}{45}\)

Bạn kia làm sai nhé :

a) \(\sqrt{\frac{25}{81}.\frac{16}{49}.\frac{169}{9}}=\sqrt{\frac{25}{81}}.\sqrt{\frac{16}{49}}.\sqrt{\frac{169}{9}}=\frac{5}{9}.\frac{4}{7}.\frac{13}{3}=\frac{260}{189}\)

=1/10+2/10+3/10+4/10+5/10+...+9/10

=1+2+3+4+...+9/10

=45/10

=4  1/2

=\(\frac{1}{10}+\frac{2}{10}+\frac{3}{10}+...+\frac{9}{10}\)

\(=\frac{\left(9+1\right).\left(9-1+1\right):2}{10}=\frac{45}{10}\)

\(A=\frac{9}{8}-\frac{8}{9}+\frac{3}{25}+\frac{1}{4}-\frac{5}{16}+\frac{19}{25}-\frac{1}{9}+\frac{2}{25}-\frac{1}{81}\)

\(A=\left(\frac{9}{8}+\frac{1}{4}-\frac{5}{16}\right)-\left(\frac{8}{9}+\frac{1}{9}-\frac{1}{81}\right)+\left(\frac{3}{25}+\frac{19}{25}+\frac{2}{25}\right)\)

\(A=\frac{17}{16}-\frac{80}{81}+\frac{24}{25}\)

\(A=\frac{33529}{32400}\)

A=1+2+3+...+99+100