Answer:
x = 7.5
Step-by-step explanation:
Given that BE is parallel to CD and intersects the 2 other sides, then it divides the 2 sides in proportion, that is
= 
, substitute values
= 
( cross- multiply )
8x = 60 ( divide both sides by 8 )
x = 7.5
Hello,
Since 3sin x-4sin^3x=sin (3x) (*****)
3sin x-4sin^3x=-1
==>sin (3x)=-1
==>3x=3π/2 +2kπ
==>x=π/2+2kπ/3, k being an integer
(*****)
sin (3x)=sin(x+2x)=sin x cos2x+cos x sin 2x
=sin x(cos²x-sin²x)+2cos²x sin x
=sin x(cos²x+2cos²x-sin²x)
=sinx(3(1-sin²x)-sin²x)
=3sin x-4sin^3x
A consistent system has at least 1 solution, it could have more.
a consistent system that has exactly 1 solution, is an independent system.
a consistent system that has infinitely many solutions, namely, both equations are really the same equation in disguise, is a dependent system.
