∫(x³+1/x)*dx=∫x³*dx+∫dx/x=x⁴/4+ln/x/+C. Ответ: x⁴/4+ln/x/+C.
1) а) 3b+(5a-7b)= 3b+5a-7b=5a-4b<span>
</span><span>б) -3q-(8p-3q)= -3q-8p+3q=-8p</span><span>
</span><span>в) 5x+(11-7x)= 5x+11-7x=11-2x</span><span>
</span><span>г) -(8c-4)+4=-8c+4+4</span>=-8c+8<span>
2) а) (2+3a)+(7a-2)=
2+3a+7a-2=10a</span><span>
</span><span>б) -(11a+b)-(12a-3b)= -11a-b-12a+3b=-23a+2b</span><span>
</span><span>в) (5-3b)+(3b-11)= 5-3b+3b-11=-6</span><span>
</span><span>г) (5a-3b)-(2+5a-3b)= 5a-3b-2-5a+3b=-2</span>
{ 7x - 0,4y = -5
{ 4x - 0,4y = 10
{ 7x -0,4y = -5
{ -0,4y = 10-4x
{ 7x +10 -4x = -5
x = -5
-0,4y = 10-4 *(-5)
y = -75
{ 7* (-5) -0,4*(-75)=-5
{ 4*(-5)-0,4*(-75)=10
{ -5=-5
{ 10=10
Ответ: (-5; -75)