X:(x-6)=9:8
x=9(x-6)/8
x=9/8x-27/4
1/8x=27/4
x=54
A1=10,2 a2=8,2
d=a2-a1=8,2-10,2=-2
a10=a1+9d=10,2-18=-7,8
<span>a^3</span><span>+b^3-</span><span>a^2b</span><span>-ab^2=</span>a^2(a-b)-b^2 (a-b)= (a-b)(a^2-b^2)=(a-b)(a+b)(a-b)= (a+b)(a-b)<span> ^2</span>
-3×-6+2×-2> 3×-9+2
-3×+2×-3×>6+2-9+2
-4×>-1
×<1
a)f'(x)=-sinx(5x+2)*5=-5sin(5x+2)