Пресметнете стойността на изразите:

[Гост]

Ако може подайте едно око на тези задачи.

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[tex]A = 5 ^{{\frac {4}{log _ {\sqrt {3}} 5}}+ \frac {1}{2} . log _{5} 4}= 5 ^{4 log _ {5} \sqrt {3} } . 5 ^{ log _{5} 4^{\frac {1}{2}}} = 5 ^{log _ {5} (\sqrt {3})^4 . 2^{\cancel {2} . \frac {1}{\cancel {2}}}} = 9.2 = 18[/tex]

[tex]B = (81 ^{\frac {1}{4} - \frac {1}{2} log _ 9 4 } + 25 ^{log _ {125} \frac {1}{8}}).49 ^{log _ {7} 2}=[/tex]
[tex]= ( \frac {3 ^{\cancel {4} . \frac {1}{\cancel { 4}}}}{9 ^{\cancel {2} .\frac {1}{\cancel {2}} log _{9} 4 }}+ 5 ^{2 log _ {5^3} 2 ^{-3} }). 7 ^{2 log _ {7} 2}=[/tex]
[tex]= (\frac {3}{4}+ 5 ^{-2 log _ {5} 2 }). 7 ^{ log _ {7} 2^2}= ( \frac 34 + \frac 14) .4 = 4[/tex]

[tex]C = 15 log _ {\frac {1}{7}}(\sqrt [5] {7} . \frac {1}{49}. 5 ^{log _ {\sqrt {5}} \sqrt[4]{49} } )= 15 log_ {\frac {1}{7}} (7 ^{\frac {1}{5}-2} . 5 ^{log _{5 ^\frac {1}{2}} 7^{2. \frac {1}{4}}})=[/tex]
[tex]=15 log _ {7 ^{-1}} 7 ^{\frac {1-10+5}{5}}=15 log _ {7 ^{-1}} 7 ^{ - \frac {4}{5}}=15. \frac 45 = 3.4=12[/tex]