Answer:
(m+2)(m-2)=m^2-4
Step-by-step explanation:
(m+2)(m-2)=m(m-2)+2(m-2)
=m^2-2m+2m-4
=m^2-4
Given data
<span>sin (x+pi/2)=cos x
</span>now using sin law
sin(a+b)=sin(a)cos(b)+cos(a)sin(b)
now using above values
sin(pi/2+x)=sin(pi/2)cos(x)+cos(pi/2)sin(x)
as we know that
sin(pi/2)=1
cos(pi/2)=0
now putting these values
sin(pi/2+x)=1*cosx+0*1
sin(pi/2+x)=cosx
hence proved that
<span>sin (x+pi/2)=cos x</span>
A,C,B
This is the answer;BC,AB,CA