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>
i believe this is it, ik it’s long but use this
Answer:
c
Step-by-step explanation:
Answer:
Option A. is correct
Step-by-step explanation:
The circumcenter is a point of intersection of all the perpendicular bisectors of a triangle.
The incenter is a point of intersection of all the angle bisectors of a triangle.
The orthocenter is a point of intersection of all the altitudes of a triangle.
The centroid is a point of intersection of all the medians of a triangle.
The incenter, orthocenter, and centroid always lie inside a triangle.
However, a circumcenter does not always lie inside a triangle.
In an acute-angled triangle, the circumcenter may lie inside or outside the triangle.
So,
Option A. is correct
A = 80/2 = 40
b = 100/2 = 50
d = 180 - (a+b)
d = 180 - (40+50)
d = 180 - 90
d = 90
