What is the differentiation of 2cos2x

2cos2x=y

dy/dx(2cos2x)=-4sin2x

d/du cosu= u'×cos'u=-u'×sinu

d/du sinu= u'×sin'u= u'×cosu

d/du tanu = u'×(1+tan²u)

d/du cotu = u'×-(1+cot²u)

proof for cosu :

cos2x= 1-2sin²x

or 2cosx²-1

or cos²x-sin²x

we will one of this fro example let's take the first one

d/dx 1-2sin²x=0-2×2(sinx)×cosx=-2sin2x

and we have 2 in the begining so its -4sin2x

right

step-by-step explanation:

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b