Докажите, (2a+3)(3a+4,5)+1 > 0

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0\ /\cdot 6" alt="6a^2+18a+14,5>0\ /\cdot 6" align="absmiddle" class="latex-formula">

0" alt="36a^2+108a+87>0" align="absmiddle" class="latex-formula">

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$(6a+9)^2 \ge 0, a\in R$

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$a\in R$

Докажите, (2a+3)(3a+4,5)+1 > 0​