Tính biểu thức hợp lý:\(11.3^7.9^{13}-9^{15}\left[\frac{2}{3}^{14}\right]^7\)
Tính hợp lý biểu thức sau:
\(\frac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}\)
ta có \(\frac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}=\frac{11.3^{29}-\left(3^2\right)^{15}}{2^2.\left(3^{14}\right)^2}\)
= \(\frac{11.3^{29}-3^{30}}{2^2.3^{28}}=\frac{3^{29}\left(11-3\right)}{2^2.3^{28}}\)
= \(\frac{3^{29}.2^3}{2^2.3^{28}}=3.2=6\)
Tính giá trị biểu thức:
\(A=\frac{11.3^{22}.3^7.9^{15}}{\left(2.3^{14}\right)^2}\)
\(A=\frac{11.3^{22}.3^7.9^{15}}{\left(2.3^{14}\right)^2}\)
\(A=\frac{11.3^{29}-3^{30}}{2^2.\left(3^{14}\right)^2}\)
\(A=\frac{3^{29}.\left(11-3\right)}{2^2.3^{28}}\)
\(A=\frac{3.2}{1.1}\)
\(A=\frac{6}{1}\)
\(A=6\)
\(\left(11.3^7.9^7-9^{15}\right):\left(2.3^{14}\right)^2\)
\(=\dfrac{11\cdot3^{21}-3^{30}}{2^2\cdot3^{28}}=\dfrac{3^{21}\left(11-3^7\right)}{2^2\cdot3^{28}}=\dfrac{-2176}{2^2\cdot3^7}=\dfrac{-2176}{8748}=\dfrac{-544}{2187}\)
35) Tính giá trị của các biểu thức
\(A=\frac{2^{10}.13+2^{10}.65}{2^8.104}\)
\(B=\frac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}\)
Bài 35 :
\(A=\frac{2^{10}.13+2^{10}.65}{2^8.104}\)
\(A=\frac{2^{10}.\left(13+65\right)}{2^8.104}\)
\(A=\frac{2^8.2^2.98}{2^8.104}\)
\(A=\frac{2^8.4.98}{2^8.4.26}\)
\(A=\frac{49}{13}\)
Vậy \(A=\frac{49}{13}\)
\(B=\frac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}\)
\(B=\frac{11.3^{29}-9^{15}}{2^2.\left(3^{14}\right)^2}\)
\(B=\frac{11.3^{29}-9^{15}}{2^2.3^{28}}\)
\(B=\frac{11.3^{29}-\left(3^2\right)^{15}}{4.3^{28}}\)
\(B=\frac{11.3^{29}-3^{30}}{4.3^{28}}\)
\(B=\frac{11.3^{29}-3^{29}.3}{4.3^{28}}\)
\(B=\frac{3^{29}.\left(11-3\right)}{4.3^{28}}\)
\(B=\frac{3^{29}.8}{4.3^{28}}\)
\(B=\frac{3^{28}.3.4.2}{4.3^{28}}\)
\(B=3.2\)
\(B=6\)
Vậy B = 6
A = 2^10 . 13 + 2^10 . 65 / 2^8 . 104
= 2^10 ( 13 + 65 ) / 2^8 . 104 = 2^10 . 78 / 2^8 . 104 = 2^8 . 2^2 . 78 / 2^8 . 104 = 2^8 . 4 . 78 / 2^8 . 104 = 2^8 . 312 / 2^8 . 104
= 312/104
= 3
B = 11 . 3^22 . 3^7 - 9^15 / ( 2.3^14)^2
= 11 . 3^29 - (3^2)^15 / ( 3.2^14)^2
= 11 . 3^29 - 3^30 / ( 3. 2 )^28
= ( 8 + 3 ) . 3^29 - 3^30 / ( 3. 2)^28
= 8 . 3^29 + 3.3^29 - 3^30 / ( 3.2)^28
= 8 . 3^29 + 3^30 - 3^30 / ( 3 . 2)^28
= 8 . 3^29 / 3^28 . 2^28
= 2^3 . 3 / 2^28
= 3/ 2^25
Tính giá trị biểu thức: \(\frac{11.3^{32}.3^7-9^{15}}{\left(2.3^{14}\right)^2}=?\)
\(\frac{11.3^{32}.3^7-9^{15}}{\left(2.3^{14}\right)^2}=\frac{11.3^{39}-3^{30}}{4.3^{28}}=\frac{3^{30}.\left(11.3^9-1\right)}{4.3^{28}}=\frac{9.\left(11.3^9-1\right)}{4}=487152\)
tính giá trị của biểu thức
A=\(\frac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}\)
Tính giá trị của biểu thức: \(A=\frac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}\)
\(a=\frac{11.3^{22}.3^7-9^{15}}{\left(2.3^{14}\right)^2}=\frac{11.3^{29}-\left(3^2\right)^{15}}{\left(2^2.3^{28}\right)}=\frac{11.3^{29}-3.^{30}}{2^2.328}\)
\(=\frac{3^{28}\left(11.3-3^2\right)}{2^2.3^{28}}=\frac{33-9}{4}=6\)
tính giá trị biểu thức
\(\frac{11.3^{22}.3^8-9^{15}}{\left[2.3^{14}\right]^2}\)
Tính giá trị của các biểu thức sau bằng cách hợp lý nhất :
a)\(\left(4\frac{5}{37}-3\frac{4}{5}+8\frac{15}{29}\right)-\left(3\frac{5}{37}-6\frac{14}{29}\right)\)
b)\(60\frac{7}{13}x+50\frac{8}{13}x-11\frac{2}{13}x\)với \(x=-8\frac{7}{10}\)
Câu a:
(4\(\frac{5}{37}\) - 3\(\frac45\) + 8\(\frac{15}{29}\)) - (3\(\frac{5}{37}\) - 6\(\frac{14}{29}\))
= 4\(\frac{5}{37}\) - 3\(\frac45\) + 8\(\frac{15}{29}\) - 3\(\frac{15}{37}\) + 6\(\frac{14}{29}\)
= (4 - 3) + (\(\frac{5}{37}-\frac{5}{37}\)) + (8 + 6) + (\(\frac{15}{29}\) + \(\frac{14}{29}\)) - 3 - \(\frac45\)
= 1 + 0 + 14 + 1 - 3 - \(\frac45\)
= 1 + 14 + 1 - 3 - \(\frac45\)
= 15 + 1 - 3 - \(\frac45\)
= 16 - 3 - \(\frac45\)
= 13 - \(\frac45\)
= \(\frac{61}{5}\)