Step-by-step explanation:
It asks you to choose values for w, the width, and evaluate the equation for each. It describes the constraint "the perimeter of 20 units" The perimeter of a rectangle is the length of all the lines of a regtangle.
Or
2L + 2W = 20 reduce this to simplest for by dividing both sides by 2;
L + W = 10, so the length plus the width is 10. Rearrange it to be W = 10 - L. Values of W can range from 1 to 9. Now sove for a few points in the function.
f(W) = 10W - W^2
3; 10(3) - 3^2 = 30 - 9 = 21.
If we look at the constraint, L = 10 - W, when the width is 3 the length must be 7. The area of a rectangle is L x W, 3 x 7 = 21. That checks against the function.
Solve for additional points.
4; 10(4) - 4^2 = 40 - 16 = 24.
If W is 4 the L is 6 and 4 x 6 = 24
Sqrt 5 because it’s an imperfect square. Fractions with integers are always rational and sqrt 9 is perfect so it is also an integer.
Step-by-step explanation:
(1 + cos θ + sin θ) / (1 + cos θ − sin θ)
Multiply by the reciprocal:
(1 + cos θ + sin θ) / (1 + cos θ − sin θ) × (1 + cos θ + sin θ) / (1 + cos θ + sin θ)
(1 + cos θ + sin θ)² / [ (1 + cos θ − sin θ) (1 + cos θ + sin θ) ]
(1 + cos θ + sin θ)² / [ (1 + cos θ)² − sin² θ) ]
Distribute and simplify:
(1 + cos θ + sin θ)² / (1 + 2 cos θ + cos² θ − sin² θ)
[ 1 + 2 (cos θ + sin θ) + (cos θ + sin θ)² ] / (1 + 2 cos θ + cos² θ − sin² θ)
(1 + 2 cos θ + 2 sin θ + cos² θ + 2 sin θ cos θ + sin² θ) / (1 + 2 cos θ + cos² θ − sin² θ)
Use Pythagorean identity:
(2 + 2 cos θ + 2 sin θ + 2 sin θ cos θ) / (sin² θ + cos² θ + 2 cos θ + cos² θ − sin² θ)
(2 + 2 cos θ + 2 sin θ + 2 sin θ cos θ) / (2 cos² θ + 2 cos θ)
(1 + cos θ + sin θ + sin θ cos θ) / (cos² θ + cos θ)
Factor:
(1 + cos θ + sin θ (1 + cos θ)) / (cos θ (1 + cos θ))
(1 + cos θ)(1 + sin θ) / (cos θ (1 + cos θ))
(1 + sin θ) / cos θ



Note:
Do the square first, and then you do mathematic operation between the parentheses. And, then do the
mathematic operation in the outside of parentheses.
Thank you.