The possible numbers that Melody could have picked are -4 and 4.
The operation that prevents us from knowing with 100% certainty the number Melody had picked is multiplication which is implied by the phrase "double the number".
Given, Let x be the number Melody had chosen.
Thus, tripling the number will give 3x, and
squaring this will result to (3x)² which is equals to 9x².
Dividing the square of the number by 2 and subtracting 30 from its quotient will give 42:
9x²/2 ₋ 30 = 42
9x²/2 = 42 ₊ 30
9x²/2 = 72
9x² = 72 × 2
9x² = 144
x² = 144/9
x² = 16
x = ±√16
x = ±4
x = ₊4 or x = 4
hence melody could have picked ₊4 or ₋4 numbers.
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Answer: x = pi/6 and x = pi/3.
Step-by-step explanation:
We have the function:
y = x + 2*cos(x)
It will have a horizontal tangent at the point where it's derivate is equal to zero.
Then first let's differentiate y.
y' = dy/dx = 1 - 2*sin(x).
Then we must find the value of x between 0 and 2*pi (or 0° and 360°)
y'(x) = 1 - 2*sin(x) = 0.
Let's solve that:
2*sin(x) = 1
sin(x) = 1/2.
We know that:
sin(30°) = 1/2.
and
Sin(120°) = 1/2
Then let's convert 30° into radians.
We know that:
pi = 180°.
Then:
pi/180° = 1.
30° = 30°*(pi/180°) = (30°/180°)*pi = (3/18)*pi = pi/6
120° = (120°/180°)*pi = (12/18)*pi = (1/3)*pi = pi/3.
Then the two values of x are: pi/6 and pi/3.
Answer:given below
Step-by-step explanation:
sqrt x^2 +81= x + 10
x^2 + 81 = (x+10)^2
x^2 + 81 = x^2 + 20x + 100
so answer is:
x^2 + 81 = x^2 +20x + 100
..HOPE IT HELPS YOU...ALL THE BEST
Answer:
42
Step-by-step explanation:
Answer:
I remember taking this too. So, the correct answer is A! I SWEAR ITS RIGHT!
Step-by-step explanation:
