![image](https://tex.z-dn.net/?f=2x%5E2%2B8x-111%3C%283x-5%29%282x%2B6%29%5C%5C%5C%5C2x%5E2%2B8x-111%3C6x%5E2%2B8x-30%5C%5C%5C%5C4x%5E2%2B81%3E0%5C%5C%5C%5C4x%5E2+%5Cgeq+0%5C%3B+%2C%5C%3B+81%3E0%5C%3B+%5C%3B+%5Cto+%5C%3B+%5C%3B+4x%5E2%2B81%3E0%5C%3B+pri%5C%3B+x%5Cin+%28-%5Cinfty%2C%2B%5Cinfty%29)
0\\\\4x^2 \geq 0\; ,\; 81>0\; \; \to \; \; 4x^2+81>0\; pri\; x\in (-\infty,+\infty)" alt="2x^2+8x-111<(3x-5)(2x+6)\\\\2x^2+8x-111<6x^2+8x-30\\\\4x^2+81>0\\\\4x^2 \geq 0\; ,\; 81>0\; \; \to \; \; 4x^2+81>0\; pri\; x\in (-\infty,+\infty)" align="absmiddle" class="latex-formula">