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>
So 3 2/3 is about 3.67 so it would go in between 3.65 and 3.7. So it would be the second answer.
Answer:
D) 4.01 miles
Step-by-step explanation:
2.87 miles from Monday + 1.14 miles =4.01 ran on Tuesday
In order to form a triangle, the third side must be at least greater than the difference of the other two sides
4 - 3 = 1 So the third side must be greater than 1 foot and the third side must be less than the sum of the other two sides
4 + 3 = 7 So, the third side must be less than 7
1 < third side < 7