(13/10)^1/2*(13/25)^1/2== (13^2/10*5^2)^1/2=
13/5*10^1/2
Это числитель
13/5*10^1/2 :10^1/2=
13/5*10^1/2*1/10^1/2=
13/5*10=13/50=26/100=0,26
![lg (x^2+2x+2)<1;](https://tex.z-dn.net/?f=lg+%28x%5E2%2B2x%2B2%29%3C1%3B)
- справедливо для любого действительного х
![lg (x^2+2x+2)<1;\\\\lg (x^2+2x+2)<lg 10;\\\\10>1;\\\\x^2+2x+2<10;\\\\\x^2+2x-8<0;\\\\(x+4)(x-2)<0;\\\\(-4;2)](https://tex.z-dn.net/?f=lg+%28x%5E2%2B2x%2B2%29%3C1%3B%5C%5C%5C%5Clg+%28x%5E2%2B2x%2B2%29%3Clg+10%3B%5C%5C%5C%5C10%3E1%3B%5C%5C%5C%5Cx%5E2%2B2x%2B2%3C10%3B%5C%5C%5C%5C%5Cx%5E2%2B2x-8%3C0%3B%5C%5C%5C%5C%28x%2B4%29%28x-2%29%3C0%3B%5C%5C%5C%5C%28-4%3B2%29)
овтет: (-4;2)
розв^язання на листочку)))
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