Х³+5х²-х-5=0
х²(х+5)-(х+5)=0
(х+5)(х²-1)=0
х=-5
х=1
х=-1
0 \\ 10-3x<0 \\ 3x>10 \\ x>\frac{10}{3} \\ x>3 \frac{1}{3} " alt="(2.5- \sqrt{6} )(10-3x)<0 \\ \\ 2.5- \sqrt{6} >0 \\ 10-3x<0 \\ 3x>10 \\ x>\frac{10}{3} \\ x>3 \frac{1}{3} " align="absmiddle" class="latex-formula">
b1+b2=60
b2+b3=84
b2=b1q
b3=b1q²
b1+b1q=60⇒b1(1+q)=60
b1q+b1q²=84 ⇒b1q(1+q)=84⇒60q=84 q=1.4 b1=60/1+q=60/2.4=25
b1=25
q=1.4
b2=35
b3=49
b1+b2+b3=25+35+49=109