以前学过的知识都忘了1.one of the solutions to the equation x^2+20=-4x

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/05/24 19:43:57

以前学过的知识都忘了
1.one of the solutions to the equation x^2+20=-4x is
A -20 B -24 C -2+4i D2+4i e 4i
2.if (2x+3)^1/2-x=0,then x=?
A 0 or -3/2 B -1+/- 2^1/2*i C 3 D -1 E 3 and -1
我主要是不知道这个i是个什么东西

i是虚数单位,i=根号下（-1）.本身-1不能开根号,但是将实数域扩展后负数也可以进行开根号运算.运算法则与根号运算一样,例如根号下-3就是（根号下3）* i；根号下-9就是3i.

以前学过的知识都忘了1.one of the solutions to the equation x^2+20=-4x 1.Find the equation of the tangent to the curve y=x^2,which write the equation of the tangent line to f(x)=x+x×x that is 英文的导数题Let f(x)=8x+20/(x^2).Then the equation of the tangent an equation of the line tangent to the graph of f(x)=x(1-2x) Find an equation of the line tangent to the graph of 4/x^4 a Find the equation of line tangent to the graph of f(x)=e+ln Find all of the solutions of th equation cosx+cos2x=0 Find the equation of the tangent line at x=2 for f(x)=√(（4x+ 英语翻译Given is the function f(x)=ln2(x-4)Find the equation of if x^2-81=19,what is the product of the solutions? 1.Express the equation x^3+6*x^2-4*x+5=0 in reduced form and