[(3x2+5)/(5x+3)]sin(2/x)的值是:()
A . 1
B . 6/5
C . 2
D . 1
lim _(xarrow infty )dfrac (3{x)^2+5}(5x+3)sin dfrac (2)(x)= __
(3) lim _(xarrow 0)dfrac (sin 2x)(sin 5x);
设=5(x)^3-(2)^x+3(e)^x+2,则=5(x)^3-(2)^x+3(e)^x+2=( ).A.=5(x)^3-(2)^x+3(e)^x+2
已知 cos (dfrac (pi )(4)+x)=dfrac (3)(5), 求sin2x的值.
(2) =sin 2xcdot (e)^x ;-|||-(3) =xcos x; ...-|||-(4) =dfrac (1)(1-{x)^2} ;-|||-(
解下列线性方程组 ) (x)_(1)+2(x)_(2)+3(x)_(3)=1 2(x)_(1)+2(x)_(2)+5(x)_(3)=2 3(x)_(1)+5(
解方程_(2)-3(x)_(3)+4(x)_(4)=-5-|||-x1- 2x3+324 =-4-|||-(x)_(1)+2(x)_(2)-5(x)_(4)=1
9、=2(x)^3-5(x)^2+3x-7=2(x)^3-5(x)^2+3x-7正确/错误9、正确/错误
解方程.(1)(9)/(10)x-2=(3)/(5) (2)x÷(2)/(5)=(3)/(8) (3)(2)/(5)+x=(18)/(25) (4)
2.解方程组 ) (x)_(1)+(x)_(2)+(x)_(3) (x)_(1)+(x)_(2)-(x)_(3)-(x)_(4)=1 5(x)_(1)+5(