Bài 40: Thực hiện phép tính:
a) $ {{4}^{{10}}}{{.8}^{{15}}}$
b) $ {{4}^{{15}}}{{.5}^{{30}}}$
c) $ {{27}^{{16}}}:{{9}^{{10}}}$
d) $ \frac{{{{{72}}^{3}}{{{.54}}^{2}}}}{{{{{108}}^{4}}}}$
e) $ \frac{{{{3}^{{10}}}.11+{{3}^{{10}}}.5}}{{{{3}^{0}}{{{.2}}^{4}}}}$
f) $ {{3}^{6}}:{{3}^{2}}+{{2}^{3}}{{.2}^{2}}$
g) $ \left( {39.42-37.42} \right):42$
h) $ 36.333-108.111$
i) $ 136.68+16.272$
k) $ 800-\left\{ {50.\left[ {\left( {18-{{2}^{3}}} \right):2+{{3}^{2}}} \right]} \right\}$
l) $ 28.\left( {231+69} \right)+72.\left( {131+169} \right)$
m) $ \left( {27.45+27.55} \right):\left( {2+4+6+…+16+18} \right)$
n) $ {{2}^{3}}.15-\left[ {115-{{{\left( {12-5} \right)}}^{2}}} \right]$
o) $ 100:\left\{ {250:\left[ {450-\left( {{{{4.5}}^{3}}-{{2}^{3}}.25} \right)} \right]} \right\}$
Bài 41: Tìm số tự nhiên x, biết:
a) $ 100-7\left( {x-5} \right)=58$
b) $ 12\left( {x-1} \right):3={{4}^{3}}+{{2}^{3}}$
c) $ 24+5x={{7}^{5}}:{{7}^{3}}$
d) $ 5.\left( {x-1} \right)-206={{2}^{4}}.4$
e) $ 5{{\left( {x-4} \right)}^{2}}-7=13$
f) $ \left( {x+1} \right)+\left( {x+2} \right)+…..+\left( {x+30} \right)=795$
g) $ {{2}^{{x+3}}}-{{3.2}^{{x+1}}}=32$
h) $ 221-{{\left( {3x+2} \right)}^{3}}=96$
Bài 42: So sánh các lũy thừa sau:
a) $ {{13}^{{14}}}\,\,\,v\grave{a}\,\,\,{{13}^{{15}}}$
b) $ {{27}^{7}}\,\,\,v\grave{a}\,\,\,{{81}^{5}}$
c) $ {{5}^{{54}}}\,\,\,v\grave{a}\,\,\,{{3}^{{81}}}$
d) $ {{2}^{{105}}}\,\,\,v\grave{a}\,\,\,{{5}^{{45}}}$