Answer:
it would be 2
Step-by-step explanation:
Answer:
rhombus, rectangle
Step-by-step explanation:
All parallelograms have two pairs of parallel sides.
A rhombus is a parallelogram. A rectangle is a parallelogram.
A trapezoid is not a parallelogram.
Answer: rhombus, rectangle
Answer:
6.28 km
Step-by-step explanation:
The formula for circumference is C = 2πr. Just plug in the radius. C = 2π2. 2 times 2 is 4. So, multiply 4π, which is 6.283185307 (rounded to the nearest billionths). Generally, you are supposed to round to the nearest hundredth. The 3 would round the 8 down, leaving 6.28. The unit used to measure the radius, so unless told otherwise by the problem, stick to km. This results in 6.28 km being your final answer.
R2(<span>cos2</span>ϕ−<span>sin2</span>ϕ)−2rcosϕ=0<span><span>r2</span>(<span>cos2</span>ϕ−<span>sin2</span>ϕ)−2rcosϕ=0</span>
<span><span><span>r2</span>cos<span>(2ϕ)</span>−2rcosϕ=0</span><span><span>r2</span>cos<span>(2ϕ)</span>−2rcosϕ=<span>0
Now </span></span></span> divide through by <span><span>r≠0</span><span>r≠0</span></span>
and get
<span><span>rcos<span>2ϕ</span>−2cosϕ=0</span><span>rcos<span>2ϕ</span>−2cosϕ=0</span></span>
or
<span><span>r=2<span><span>cosϕ</span><span>cos<span>2ϕ</span></span></span></span><span>r=2<span><span>cosϕ</span><span>cos<span>2<span>ϕ</span></span></span></span></span></span>