(tan²(<em>θ</em>) cos²(<em>θ</em>) - 1) / (1 + cos(2<em>θ</em>))
Recall that
tan(<em>θ</em>) = sin(<em>θ</em>) / cos(<em>θ</em>)
so cos²(<em>θ</em>) cancels with the cos²(<em>θ</em>) in the tan²(<em>θ</em>) term:
(sin²(<em>θ</em>) - 1) / (1 + cos(2<em>θ</em>))
Recall the double angle identity for cosine,
cos(2<em>θ</em>) = 2 cos²(<em>θ</em>) - 1
so the 1 in the denominator also vanishes:
(sin²(<em>θ</em>) - 1) / (2 cos²(<em>θ</em>))
Recall the Pythagorean identity,
cos²(<em>θ</em>) + sin²(<em>θ</em>) = 1
which means
sin²(<em>θ</em>) - 1 = -cos²(<em>θ</em>):
-cos²(<em>θ</em>) / (2 cos²(<em>θ</em>))
Cancel the cos²(<em>θ</em>) terms to end up with
(tan²(<em>θ</em>) cos²(<em>θ</em>) - 1) / (1 + cos(2<em>θ</em>)) = -1/2
(3,-1)? i believe that's what it would be
Let x be the amount of Ann money, y be Jessica's money and z Mary money.
30% of z equates 0.3*z.
Ann has 30% less than z so: x = z - 0.3z = 0.7z.
70% of z equates 0.7z.
"Jessica has 70% more than Mary " we deduce the equation: y =z+0.7z= 1.7z.
Signe the total is $102, we deduce the equation x+y+z = 102.
x=0.7z and y=1.7z then 0.7z+1.7z+z=102, therefore 3.4z=102 then
z =102/3.4 = $30.
x=0.7*30= 21 and y=1.7*30=51.
Ann has $21, Mary has $30 and Jessica has $51.
2x+2y =50
2(7)+ 2(3)=50
14+6 =50
20=/=50
This is false because when you substitute the variables with their numbers and then multiply and add, your answer does not equal 50
Answer:
The volume of the sphere is 113.04 yd³
Step-by-step explanation:
