Since sin(2x)=2sinxcosx, we can plug that in to get sin(4x)=2sin(2x)cos(2x)=2*2sinxcosxcos(2x)=4sinxcosxcos(2x). Since cos(2x) = cos^2x-sin^2x, we plug that in. In addition, cos4x=cos^2(2x)-sin^2(2x). Next, since cos^2x=(1+cos(2x))/2 and sin^2x= (1-cos(2x))/2, we plug those in to end up with 4sinxcosxcos(2x)-((1+cos(2x))/2-(1-cos(2x))/2)
=4sinxcosxcos(2x)-(2cos(2x)/2)=4sinxcosxcos(2x)-cos(2x)
=cos(2x)*(4sinxcosx-1). Since sinxcosx=sin(2x), we plug that back in to end up with cos(2x)*(4sin(2x)-1)
Answer:
1/2
Step-by-step explanation:
there ARE ONLY TWO GENDERS
THE dog can be male or female =
sum genders = 2
probability of been a male = 1/2
Answer:
Distinct ways in which they all can form the teams for the class = n(n-1)
Step-by-step explanation:
Total numbers of students = n (even number)
Number of student in each team = 2
Number of distinct ways are there to form the teams for the class:
where = n = number of elements = n
k = number of elements choose = 2
