а) 6²-(7(n+2))²=(6-7(n+2))(6+7(n+2))= (-8-7n)(20+7n)= -(8+7n)(20+7n)
б) ((x+5)-3(x-1))((x+5)+3(x-1)) = (8-2x)(4x+2)
в) (2(3а²+2b)-(3a²-2b))(2(3a²+2b)+(3a²-2b)) = (3a²+6b)(9a²+2b)
1/ x0+deltax=x1=4.01 f(x0)=1+2*4=9
f(x1)=1+2*4.01=1+8.02=9.02 delta f(x) =9.02-9=0.2
2/ f(x)=-5x+1.6 f(x0)=-5(-5)+1.6=25+1.6=26.6
x1=-5-0.1=-5.1 f(-5.1)=-0.55(-5.1)+1.6=27.1
delta f(x)=27.1-26.6=0.5
Да так как 75\%+15\% =100\%
(x²-3x)/(x³-3x²-9x+27)=x*(x-3)/((x²*(x-3)-9*(x-3))=x*(x-3)/((x-3)(x²-9)=x/(x²-9).