几道微积分题目!求过程!
发布网友
发布时间:2024-10-21 23:36
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热心网友
时间:2024-10-26 12:22
1
lim(x->0) [(1+cosx)^x -2^x]/sinx^2
=lim(x->0)2^x[(cos(x/2)^2x-1]/(sinx)^2
=lim(x->0)2^x[(cos(x/2)^x/sinx)^2-1/(sinx)^2]
lim( x->0) ((cosx/2)^x/sinx)^2-1/sinx^2=0
=0
2 B
x<x^2 , x>1
x>x^2, x<1
3
=ln2
f(x)=2^x f'(x)=ln2*2^x f'(0)=ln2
4
y=a^x+√(1-a^(2x))arccosa^x
y'=lna*a^x + [-lnaa^(2x)/√(1-a^2x)]arccosa^x -lna*a^x
dy=y'dx
5
x^2+y^2=arctan(y/x)
2x+2yy'=(y'/x-y/x^2)/(1+y^2/x^2)
2x+y/(x^2+y^2)=y'(x/(x^2+y^2)-2y)
y'=[2x+y/(x^2+y^2)]/ [ x/(x^2+y^2)-2y ]
热心网友
时间:2024-10-26 12:20
第2题 F(x)=x (0<x<=1) F(x)=x^2 (1<x<2)
F'(x)=1(0<x<1) F'(x)=2x (1<x<2) x=1时连续但不可导,所以x取不到1 选D
热心网友
时间:2024-10-26 12:26
1
lim(x->0) [(1+cosx)^x -2^x]/sinx^2
=lim(x->0)2^x[(cos(x/2)^2x-1]/(sinx)^2
=lim(x->0)2^x[(cos(x/2)^x/sinx)^2-1/(sinx)^2]
lim( x->0) ((cosx/2)^x/sinx)^2-1/sinx^2=0
=0
2 B
x<x^2 , x>1
x>x^2, x<1
3
=ln2
f(x)=2^x f'(x)=ln2*2^x f'(0)=ln2
4
y=a^x+√(1-a^(2x))arccosa^x
y'=lna*a^x + [-lnaa^(2x)/√(1-a^2x)]arccosa^x -lna*a^x
dy=y'dx
5
x^2+y^2=arctan(y/x)
2x+2yy'=(y'/x-y/x^2)/(1+y^2/x^2)
2x+y/(x^2+y^2)=y'(x/(x^2+y^2)-2y)
y'=[2x+y/(x^2+y^2)]/ [ x/(x^2+y^2)-2y ]
热心网友
时间:2024-10-26 12:24
第2题 F(x)=x (0<x<=1) F(x)=x^2 (1<x<2)
F'(x)=1(0<x<1) F'(x)=2x (1<x<2) x=1时连续但不可导,所以x取不到1 选D