`(d^(20))/(dx^(20))(2cosxcos3x)` is equal to........

(d^(20)y)/(dx^(20))(2cosxcos3x)is equal to 2^(20)(cos2x-2^(20)os3x) 2^(20)(cos2x+2^(20)cos4x) 2^(20)(sin2x+2^(20)sin4x) 2^(20)(sin2x-2^(20)sin4x)

(d^(20))/(dx^(20))(2cos x cos3x) is equal to (a) 2^(20)(cos2x-2^(20)cos3x)(b)2^(20)(cos2x+2^(20)cos4x)(c)2^(20)(cos2x+2^(20)sin4x)(d)2^(20)(sin2x-2^(20)sin4x)

(d^(20)y)/(dx^(20))(2cosxcos3x)i se q u a l to a)2^(20)(cos2x-2^(20)os3x) b)2^(20)(cos2x+2^(20)cos4x) c)2^(20)(sin2x+2^(20)sin4x) d)2^(20)(sin2x-2^(20)sin4x)

(d ^(20))/(dx ^(20)) [ 2 cos x cos 3x]=

(d^(20))/(dx^(20))(2cosxcos3x)= 2^(20)(cos2x-2^(20)cos4x) (b) 2^(20)(cos2x+2^(20)cos4x) (c) 2^(20)(sin2x+2^(20)sin4x) (d) 2^(20)(sin2x-2^(20)sin4x)

(d^(20))/(dx^(20))(2cos x cos3x)=2^(20)(cos2x-2^(20)cos4x)(b)2^(20)(cos2x+2^(20)cos4x)(c)2^(20)(sin2x+2^(20)sin4x)(d)2^(20)(sin2x-2^(20)sin4x)

If (d^(2)x)/(dy^(2)) ((dy)/(dx))^(3) + (d^(2) y)/(dx^(2)) = k , then k is equal to

If (d^(2)x)/(dy^(2)) ((dy)/(dx))^(3) + (d^(2) y)/(dx^(2)) = k , then k is equal to

If (d^(2)x)/(dy^(2)) ((dy)/(dx))^(3) + (d^(2) y)/(dx^(2)) = k , then k is equal to

If (d^(2)x)/(dy^(2)) ((dy)/(dx))^(3) + (d^(2) y)/(dx^(2)) = k , then k is equal to