A) 2^30 : 2^27 = 2^3=8 (т.к. 8 = 2^3)
b) 4.7^1+ (-3)^3=4.7 -27= - 22.3 (если правильно понял запись)
<span>m(t) = m0·2</span><span>^(−t/T)</span>
<span>m0=200 <span>мг
</span></span><span>T=3 мин
</span>m(t) = <span>25 <span>мг
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t - ?
Подставляем в формулу </span></span><span>m(t) = m0·2<span>^(−t/T) </span>значения </span>m0, Т и m(t) :
<span>25 = 200·2</span><span><span>^(</span><span>− t/3)
</span></span>25 = 200/2<span>^(t/3)</span>
2<span>^(<span>t/3) = 200/25
</span></span>2<span>^(t/3) = 8</span>
2<span>^(<span>t/3) = 2³
</span></span><span>t/3 = 3
</span><span>t = 9
Ответ: 9 минут
</span>
(2sqrt(12))^2/24=4*12/24=2
ответ: 2.
<span>lg (x-5)^2=0</span><span>2lg (x-5)=0 :2</span>lg (x-5)=0
(x-5)=10^0
x-5=1
x=6