15/7x-10/7=x+2
15/7-x=2+10/7
8/7x=24/7
x=3
<span>1) f(x)=3x/x+3+7cosx</span>
<span><span>f(x)=3+3+7cosx</span></span>
<span><span><span>f(x)=6+7cos0</span></span></span>
<span><span><span><span>f(x)=6+7*1</span></span></span></span>
<span><span><span><span>f(x) = 13</span></span></span></span>
Ответ:13
2)
<span>a) у=</span><span>√x^2+1/x</span>
y=x+1/x, D(y): x≠0
При х=1 ⇒ y=1+1/1=2 имеем точку (1; 2)
При х = -1 ⇒ у=-1+(-1)/1=-2 точка (-1; -2)
При х=2 ⇒ у=2+1/2=2+0,5=2,5 - точка (2; 2,5)
и так дальше
По точкам можно нариссовать график.
3 ^ x * 5 ^ y = 3 ¹ * 5² = 3 * 25 = 75
3 ^ y * 5 ^ x = 3 ² * 5 ¹ = 9 * 5 = 45
x=1
y=2
<span>(x+3) (x</span><span>²</span><span>-3x+9)=x</span><span>³+27</span>-----------------------------------------------<span>
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