Докажите тождество: № 114

[latex]\displaystyle \textbf{1)}\\\\(3a-5b)(a^2+2ab-4b^2)-(3a-5b)(a^2+2ab-7b^2)=\\\\=(3a-5b)[(a^2+2ab-4b^2)-(a^2+2ab-7b^2)]=\\\\=(3a-5b)(a^2+2ab-4b^2-a^2-2ab+7b^2)=\\\\=3b^2(3a-5b)\\\\\textbf{2)}\\\\(2a-1)(6b^2+3b-8)+(1-2a)(6b^2+3b-10)=\\\\=(2a-1)(6b^2+3b-8)-(2a-1)(6b^2+3b-10)=\\\\=(2a-1)[(6b^2+3b-8)-(6b^2+3b-10)]=\\\\=(2a-1)(6b^2+3b-8-6b^2-3b+10)=\\\\=2(2a-1)=4a-2[/latex]