用R程序编程求下列的值，正确的命令是 （ ）[img=273x30]180398c76b70239.png[/img]
A: x<-log(2);y<-log(3);100^(2*x-y)
B: x<-log10(2);y<-log10(3);100^(2*x-y)
C: x<-log10(2);y<-log10(3);100^(2x-y)
D: x<-log(2);y<-log(3);100^(2x-y)
A: x<-log(2);y<-log(3);100^(2*x-y)
B: x<-log10(2);y<-log10(3);100^(2*x-y)
C: x<-log10(2);y<-log10(3);100^(2x-y)
D: x<-log(2);y<-log(3);100^(2x-y)
举一反三
- 实验命令“ syms x y; z=2*exp(x*y)+log(x+y)； zx=diff(z,'x')”的结果是【】. A: 2*exp(x*y)+log(x+y); B: 2* y*exp(x*y)+1/(x+y); C: 2*x*exp(x*y)+1/(x+y); D: 无结果.
- <img src="http://edu-image.nosdn.127.net/E6A0628104FCB0F521FBF2AAAC7F1968.png?imageView&thumbnail=890x0&quality=100" style="width: 558px; height: 33px;" />? syms xy=log(1/x*x+exp(x))+sin(1-x^2)dy/dx=diff(y,x)|syms xy=log(1/x/x+exp(x))+sin(1-x^2)dydx=diff(y,x)|syms xy=log(1/x/x+exp(x))+sin(1-x)^2dydx=diff(y,x)|syms xy=log(1/x/x+exp^x)+sin(1-x^2)dydx=diff(y,x)
- 下列函数为偶函数的是（ ）。 A: \( y = {2{e}^{2x}} - {2{e}^{ - 2x}} + \sin x \) B: \( y = {\log _a} { { 1 - x} \over {1 + x}} \) C: \( y = { { {e^x} + {e^{ - x}}} \over 2} \) D: \( y = 3{x^2} - {x^3} \)
- 设\(z = {\log _y}x\)，则\({z_y} = { { \ln x} \over {y { { \ln }^2}y}}\).
- 下列函数在区间(0,+∞)上为增函数的是() A: y=cosx B: y=2^x C: y= 2-x^2 D: y=log(1/3)x