<span>10(х-4)+4(х-10)=2
10x-40+4x-40=2
14x-80-2=0
14x-82=0
14x=82
x=82/14=41/7=5 6/7</span>
5x+48:4= 20:10+2*10
5х+48:4= 22
5х+12=22
5х=22-12
5х=10
Х=10:5
Х=2
1) y'=5tg^4(3x^4-13)* 1/cos^2(3x^4-13)* 12x^3
2) y'=4ctg^3(5x^3+6)*1/-sin^2(5x^3+6)*15x^2
<span>3)y' =4cos^3(6x^2+9)* (-sin(6x^2+9))*12s</span>