Answer:
Verified below
Step-by-step explanation:
We want to show that (Cos2θ)/(1 + sin2θ) = (cot θ - 1)/(cot θ + 1)
In trigonometric identities;
Cot θ = cos θ/sin θ
Thus;
(cot θ - 1)/(cot θ + 1) gives;
((cos θ/sin θ) - 1)/((cos θ/sin θ) + 1)
Simplifying numerator and denominator gives;
((cos θ - sin θ)/sin θ)/((cos θ + sin θ)/sin θ)
This reduces to;
>> (cos θ - sin θ)/(cos θ + sin θ)
Multiply top and bottom by ((cos θ + sin θ) to get;
>> (cos² θ - sin²θ)/(cos²θ + sin²θ + 2sinθcosθ)
In trigonometric identities, we know that;
cos 2θ = (cos² θ - sin²θ)
cos²θ + sin²θ = 1
sin 2θ = 2sinθcosθ
Thus;
(cos² θ - sin²θ)/(cos²θ + sin²θ + 2sinθcosθ) gives us:
>> cos 2θ/(1 + sin 2θ)
This is equal to the left hand side.
Thus, it is verified.
Answer:
i did the first
Step-by-step explanation:
1st way
Standard form: a(X-h)²+k = ( -2/3X² -16/3X -32/3) +32/3 -17/3 = -2/3(X +4)² +5
y = -2/3*X^2-16/3*X-17/3
X = -4 ±√( 15/2) = -6.7386, or -1.2614
Axis of symmetry: X= -4; Vertex (maximum)=(h,k)=( -4, 5); y-intercept is (0,-5.66666666667)
two real roots: X=-1.2613872124776866 and -6.738612787477313
X + y = 23000
x.08 + y.09 = 2040
x = 23000 - y
(23000 - y) .08 + y.09 = 2040
1840 - .08y + .09y = 2040
Simplify
.01y = 200
Simplify
Y = 20000
X + 20000 = 23000
X = 3000
CHECK: .08x + .09(20000) = 2040
.08x + 1800 = 2040
Simply .08x = 240
X = 3000
Answer:
answer is 11 feet is the correct answer
