First we use sin(a+b)= sinacosb+sinbcosa
and cos(a+b)=cosa cosb -sinasinb
tan(x+pi/2)= sin(x+pi/2) / cos(x+pi/2)
and sin(x+pi/2) = sinxcospi/2 + sinpi/2cosx =cosx,
<span>cos(x+pi/2) = cosxcospi/2- sinxsinpi/2= - sinx,
</span> because <span>cospi/2 =0, </span>and <span>sinpi/2=1
</span><span>=tan(x+pi/2)= sin(x+pi/2) / cos(x+pi/2)= cosx / -sinx = -1/tanx = -cotx
</span>from where <span>tan(x+pi/2)=-cotx</span>
Answer: 7 1/2
Step-by-step explanation:
Answer:
x = 11
Step-by-step explanation:
ΔLKM is an equilateral because a triangle with all 3 sides that are congruent is an equilateral triangle.
Angles in an equilateral triangle are all 60°.
Thus, ∠L = 60°.
=> 3x + 27 = 60
=> 3x = 33
=> x = 11
