If `f(x)=(cosx+isinx)(cos2x+isin2x)(cos3x+isin3x)ddot(cosn x+isinn x)` and `f(1)=1` , then `f"(1)` is equal to `(n(n+1))/2` (b) `{(n(n+1))/2}^2` (c) `-{(n(n+1))/2}^2` (d) none of these

If f(x)=(cosx+isinx)(cos2x+isin2x)(cos3x+isin3x)......(cosn x+isinn x) and f(1)=1 ,then f^('')(1) is equal to

If quad f(x)=(cos x+i sin x)(cos2x+i sin2x)(cos3x+i sin3x)cos nx+i sin nx and f(1)=1, then f(1) is equal to (n(n+1))/(2) (b) {(n(n+1))/(2)}^(2)(c)-{(n(n+1))/(2)}^(2) (d) none of these

If f(x)=(cos x+i sin x)(cos2x+i sin2x)(cos3x+i sin3x)......(cos nx+i sin n and f(1)=1, then f^(11) is equal to (a) (n(n+1))/(2) (b) {(n(n+1))/(2)}^(2)(C)-{(n(n+1))/(2)}^(2) (d) none of these

The function f(x)=(cosx+isinx)(cos3x+isin3x)...{cos(2n-1)x+isin(2n-1)x} , then f'(x) is equal to

If f(x) = (cos x + i sin x)(cos 3x + i sin 3x) ….(cos (2n - 1)x + i(sin(2n - 1)x) , then f^(11)(x) is

If f(x)=(cosx+isinx)(cos3x+isin3x)...(cos(2n-1)x+isin(2n-1)x) then f''(x) is

If f(x) is given by f(x)=(cosx+i sinx)(cos3x+isin3x) ......... ....... [cos(2n-1)x+isin(2n-1)x] , then f''(x) is equal to

If f(x) is given by f(x)=(cosx+i sinx)(cos3x+isin3x) ......... ....... [cos(2n-1)x+isin(2n-1)x] , then f''(x) is equal to

If f(x) is given by f(x)=(cosx+i sinx)(cos3x+isin3x) ......... ....... [cos(2n-1)x+isin(2n-1)x] , then f''(x) is equal to

If f(x) is given by f(x) = (cosx+i sinx)(cos3x+isin3x)......[cos(2n-1)x+isin(2n-1)x] then f''(x) is equal to a. n^(3)f(x) b. -n^(4)f(x) c. -n^(2)f(x) d. n^(4)f(x)