`cos(n+1)Acos(n+2)A+sin(n+1)Asin(n+2)A=`

cos (n + 1) A cos (n + 2) A + sin (n + 1) A sin (n + 2) A =

The determinant Delta=|(a^2,a,1),(cos(nx),cos (n + 1) x,cos(n+2) x),(sin(nx),sin (n +1)x,sin (n + 2) x)| is independent of

The determinant Delta=|(a^2,a,1),(cos(nx),cos (n + 1) x,cos(n+2) x),(sin(nx),sin (n +1)x,sin (n + 2) x)| is independent of

Prove that: sin(n+1)A sin(n+2)A+cos(n+1)A cos(n+2)A=cos A

(sin (n +1) A +2 sin n A + sin ( n -1) A )/( cos (n +1) A - cos ( n -1) A ) =

Prove that: sin(n+1)As in(n+2)A+cos(+1)A cos(n+2)A=cos A

The value of the determinants |{:(1,a,a^(2)),(cos(n-1)x,cos nx , cos(n+1)x),(sin(n-1)x , sin nx , sin(n+1)x):}| is zero if

The value of the determinants |{:(1,a,a^(2)),(cos(n-1)x,cos nx , cos(n+1)x),(sin(n-1)x , sin nx , sin(n+1)x):}| is zero if

The value of the determinants |{:(1,a,a^(2)),(cos(n-1)x,cos nx , cos(n+1)x),(sin(n-1)x , sin nx , sin(n+1)x):}| is zero if

The value of the determinants |{:(1,a,a^(2)),(cos(n-1)x,cos nx , cos(n+1)x),(sin(n-1)x , sin nx , sin(n+1)x):}| is zero if