作业帮the function f is defined by f(X)=cosec x + tan2x ,A.show that the roots of f(x)=0 satisfy the pls solve the function f is defined by f(X)=cosec x + tan2x ,A.show that the roots of f(x)=0 satisfy the equation2cos^3 (x) -2cos^2(X)-2cosx+1=0
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/11 22:31:50
the function f is defined by f(X)=cosec x + tan2x ,A.show that the roots of f(x)=0 satisfy the pls solve the function f is defined by f(X)=cosec x + tan2x ,A.show that the roots of f(x)=0 satisfy the equation2cos^3 (x) -2cos^2(X)-2cosx+1=0
the function f is defined by f(X)=cosec x + tan2x ,A.show that the roots of f(x)=0 satisfy the
pls solve
the function f is defined by f(X)=cosec x + tan2x ,
A.show that the roots of f(x)=0 satisfy the equation
2cos^3 (x) -2cos^2(X)-2cosx+1=0
the function f is defined by f(X)=cosec x + tan2x ,A.show that the roots of f(x)=0 satisfy the pls solve the function f is defined by f(X)=cosec x + tan2x ,A.show that the roots of f(x)=0 satisfy the equation2cos^3 (x) -2cos^2(X)-2cosx+1=0
2(cosx)^3-2(cosx)^2-2cosx+1=2cosx{(cosx)^2-1]-cos2x=-2sinxcosxsinx-cos2x
=-sin2xsinx-cos2x
=-(tan2xsinx+1)cos2x
=-(tan2x+cosecx)cos2xsinx
if 2cos^3 (x) -2cos^2(X)-2cosx+1=0,
then tan2x+cosecx=0 or cos2x=0 or sinx=0
if tan2x+cosecx=0
then 2cos^3 (x) -2cos^2(X)-2cosx+1=0