A=15^3.45^4:25^2.9^4
3.45 x 123 + 4 x 3.45 -3.45 x 27 đề bài :tính nhanh
các bạn làm nhanh giúp,mình đang cần gấp
= 3,45 x (123 + 4 - 27)
= 3,45 x 100
= 345
HT
Rut gon roi tinh: ( \(\frac{12^2}{4^2.6^2}\) - \(\frac{15^3}{25^2.6^2}\) - \(\frac{8^2.9^2}{4^3.6^4}\) )
Thực hiện phép tính: \(A=\frac{3^{15}.2^{22}+6^{16}.4^4}{2.9^9.8^7-7.27^5.2^{23}}\)
Rút gọn biêu thức
A=3^2.45^4-15^3.9^3/3^3.45^4-5^4.3^10
B=6^30.3^11.7-2^31.5.3^40/2^28.17.3^38-6^27.3^11
C=35.27^8+70.9^11/15.81^6-60.3^20
D=4^6.6^7-9^3.8^6/12^5.2^8+18^3.32^3
Rút gọn
a) \(\frac{2^{13}.3^7}{2^{15}.3^2.9}\)
b) \(\frac{4^{10}+8^4}{4^5+8^6}\)
a)\(=\frac{3^7}{2^2.3^4}=\frac{3^3}{2^2}=\frac{27}{4}\)
b)\(=\frac{2^{20}+2^{12}}{2^{10}+2^{18}}=\frac{2^{12}\left(2^8+1\right)}{2^{10}\left(1+2^8\right)}=\frac{2^{12}}{2^{10}}=2^2=4\)
Cho:
a) A = 5 . 4^15 . 9^9 - 4 . 3^20 . 8^9 và B = 5.2^9.6^19-7.2^29.27^6
Tính A : B
b) C = 2181.729+243.81.27 và D = 3^2.9^2.243+18.243.324+723.729
\(A=5.4^{15}.9^9-4.3^{20}.8^9\\ =5.2^{30}.3^{18}-3^{20}.2^{29}\\ B=5.2^9.6^{19}-7.2^{29}.27^6\\=5.2^{28}.3^{19}-7.2^{^{29}}.3^{18}\\ \Rightarrow A:B=\left(5.2^{30}.3^{18}-3^{20}.2^{29}\right):\left(5.2^{28}.3^{19}-7.2^{^{29}}.3^{18}\right)\\ =\dfrac{2^2-3^2}{3-7}=\dfrac{4-9}{-4}=\dfrac{5}{4}\)
Bài 4 : Tính giá trị các biểu thức :
a. A= 22 - (-32)3 + 4-2 .16-2.52 .
b. B= (23 : 1/2) . 1/2+3-2.9-7. (14/25)0+5 .
c. C= 2-3 + (52)3.5-3+4-3 . 16 -2.32-105. (24/51)0 .
d. D= (2-3.1/2-2).2/3+4-2.8-7.(17/23)0+19 .
A=\(2^2-9^3+4^{-2}.16-2.5^2\)
\(=4-729+1-50=-774\)
B=\(\left(2^3.2\right).\dfrac{1}{2}+3^{-2}.3^2-7.1+5\)
\(B=2^4.\dfrac{1}{2}+1-7+5=8+1-7+5=7\)
C = 2-3 + (52)3.5-3 + 4-3.16 - 2.32 - 105.(\(\dfrac{24}{51}\))0
C = \(\dfrac{1}{8}\) + 56.5-3 + 4-3.42 - 2.9 - 105.1
C = \(\dfrac{1}{8}\) + 53 + \(\dfrac{1}{4}\) - 18 - 105
C = (\(\dfrac{1}{8}\) + \(\dfrac{1}{4}\)) - (105 - 125 + 18)
C = \(\dfrac{3}{8}\) - (-20 + 18)
C = \(\dfrac{3}{8}\) + 2
C = \(\dfrac{19}{8}\)
D = 2-3 . \(\dfrac{1}{2^{-2}}\).\(\dfrac{2}{3}\) + 4-2.8 - 7. (\(\dfrac{17}{23}\))0 + 19
D = 2-1.\(\dfrac{2}{3}\) + \(\dfrac{1}{16}\).8 - 7.1 + 19
D = \(\dfrac{1}{3}\) + \(\dfrac{1}{2}\) - 7 + 19
D = \(\dfrac{5}{6}\) + (19 - 7)
D = \(\dfrac{5}{6}\) + 12
D = \(\dfrac{77}{6}\)
a,\(\frac{2^{13}.3^7}{2^{15}.3^2.9^2}\)
b,\(\frac{2^{15}.9^4}{6^6.8^3}\)
\(\frac{2^{13}.3^7}{2^{15}.3^2.9^2}=\frac{2^{13}.3^7}{2^{15}.3^6}=\frac{3}{4}\)
\(\frac{2^{15}.9^4}{6^6.8^3}=\frac{2^{15}.3^8}{3^6.2^{15}}=3^2=9\)
Tìm x : x-3.45=90.5:15
\(x-3,45=\frac{90,5}{15}=\frac{181}{30}\)
=> \(x=\frac{181}{30}+3,45=\frac{569}{60}\)
x - 3 . 45 = 90 . 5 : 15
x - 135 = 450 : 15
x - 135 = 30
x = 30 + 135
x = 165
Vậy x = 165