1. (ax+b)(cx+d)=?
(ax+b)(cx+d)
=acx^2+adx+bcx+bd
=acx^2+(ad+bc)x+bd
希望对你有帮助
2. (ax+b)(cx+d)
acx^2+(ad+bc)x+bd
3. ax-b=cx+b
ax-cx=2b
(a-c)x=2b
若a=c,b≠0,无解
若a=c,b=0,有无数解
若a≠c,x=2b/(a-c)
4. ax-bx=?
ax-bx=x(a-b)
不懂可追问,有帮助请采纳,谢谢!
5. ∫ x/(ax+b)dx
答:∫ x/(ax+b) dx= (1/a^2)*∫ ax/(ax+b) d(ax+b)=(1/a^2) ∫ (ax+b-b) /(ax+b) d(ax+b)=(1/a^2) ∫ 1 -b/(ax+b) d(ax+b)=(1/a^2)* [ax+b-b*ln |ax+b| ] + C1=x / a -(b/a^2)*ln |ax+b| +C
6. (ax+b)(cx+d)=?
(ax+b)(cx+d)
=acx^2+(ad+bc)x+bd
7. x-ax-bx-cx-d
f(x)=ax^3+bx^2+cx+d,
f '(x)=3ax^2+2bx+c ,
由已知,f '(x)=0 有根 x=-1 和 x=1 ,
因此有 f '(x)=3a(x+1)(x-1)=3ax^2-3a ,
由此得 ①2b=0 ,②c=-3a ,
又 ③f(-1)=-a+b-c+d=5 ,④f(1)=a+b+c+d=1 ,
由①②③④可解得 a=1,b=0,c=-3 ,d=3 .
8. ∫ x/(ax+b)dx
答:∫ x/(ax+b) dx= (1/a^2)*∫ ax/(ax+b) d(ax+b)=(1/a^2) ∫ (ax+b-b) /(ax+b) d(ax+b)=(1/a^2) ∫ 1 -b/(ax+b) d(ax+b)=(1/a^2)* [ax+b-b*ln |ax+b| ] + C1=x / a -(b/a^2)*ln |ax+b| +C