Answer:
(1) x^2 is greater than 1.
(2) x is greater than -1.
(1) x^2 is greater than 1 --> x2>1x2>1 --> x<−1x<−1 or x>1x>1. Sufficient.
(2) x is greater than -1 --> x>−1x>−1. Not sufficient.
Answer:
2,5
Step-by-step explanation:
(1+3)/2, (4+6)/2
Let,
Harry's age - x then Nick is 7x.
After 6 years, Harry is x+6 and Nick is 7x+6
So, 7x+6= 5(x+6)=> 2x = 30-6X = 12
In 6 years, Harry will be 12+6 = 18 years (Ans)
Answer:
7 feet is the length of the blade of the windmill.
Step-by-step explanation:
We have the equation
h = 7 sin(pi/21t) + 28 ------ eq1
At time 't' = 0, the end of the blade is pointing to the right parallel to the ground meaning it is at the same height as the other end. (Ф = 0°)
So, by calculating the maximum height of this end at Ф = 90°. we can calculate the length of the blade.
Now, we know that a general model equation of a circular simple harmonic motion is represented as : y = A sinωt + k ----- eq2
Where A is the amplitude that is, maximum displacement from mean to maximum position.
ω is the angular frequency.
Comparing eq1 and eq2:
A = 7
so the difference in blades end height at Ф = 0° and Ф = 90° is 7 feet.
Hence, the length of the blade is 7 feet.
I think it means grater or less ? Or positive or negative?