Answer:
120
Step-by-step explanation:
From 20, choose 3:
₂₀C₃ = 120
Here we use combinations instead of permutations because the order doesn't matter.
Answer:
weight * (4 / 5) = 30
weight * .8 = 30
weight = 30 / .8
weight = 37.5 pounds
Step-by-step explanation:
Answer:
hasnt happened to me
Step-by-step explanation:try restarting your device
Answer:
x =pi/2,3pi/2
Step-by-step explanation:
sin²(x) - cos²(x) - sin²(x) = 0
Simplify
sin²(x) - sin²(x) = 0
Leaving us with
- cos²(x) = 0
Divide each side by -1
- cos²(x/-1 = 0/-1
cos²(x) = 0
Take the square root of each side
sqrt( cos²(x)) = sqrt(0)
cos(x) = 0
Taking the inverse cos of each side
cos^-1(cos(x)) = cos^-1(0)
x = pi/2 x = 3pi/2
