Answer: cos(x)
Step-by-step explanation:
We have
sin ( x + y ) = sin(x)*cos(y) + cos(x)*sin(y) (1) and
cos ( x + y ) = cos(x)*cos(y) - sin(x)*sin(y) (2)
From eq. (1)
if x = y
sin ( x + x ) = sin(x)*cos(x) + cos(x)*sin(x) ⇒ sin(2x) = 2sin(x)cos(x)
From eq. 2
If x = y
cos ( x + x ) = cos(x)*cos(x) - sin(x)*sin(x) ⇒ cos²(x) - sin²(x)
cos (2x) = cos²(x) - sin²(x)
Hence:The expression:
cos(2x) cos(x) + sin(2x) sin(x) (3)
Subtition of sin(2x) and cos(2x) in eq. 3
[cos²(x)-sin²(x)]*cos(x) + [(2sen(x)cos(x)]*sin(x)
and operating
cos³(x) - sin²(x)cos(x) + 2sin²(x)cos(x) = cos³(x) + sin²(x)cos(x)
cos (x) [ cos²(x) + sin²(x) ] = cos(x)
since cos²(x) + sin²(x) = 1
Answer:
48 questions.
Step-by-step explanation:
x is for the unknown variable, the number you are trying to figure out.
12= 25%x
if you convert to a fraction, 12 is 1/4 of x. if you then multiply your answer by 4, 12 is 25% of 48.
to figure this out you can also ask, 12 is 25% of what number?
The answer is A
in a y-int your x coordinate is always going to be 0
Answer: A
Step-by-step explanation: So, first of all, this is a linear graph, which is represented by the equation y = mx + b.
b = y-intercept. The y-intercept is the point in which the line crosses the y axis. Assuming this graph has units that go up by 1, the y- intercept for this line is 2, which eliminates choices B and C.
This graph is going down, which means it is negative, so the format should be -mx + b, which is answer choice A. Hope this helps! :)
Answer:
see explanation
Step-by-step explanation:
- 17 = - 2 - x ( add 2 to both sides )
- 15 = - x ( multiply both sides by - 1 )
15 = x
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- 9 = - 15 ( add 9 to both sides )
= - 6 ( multiply both sides by 3 to clear the fraction )
x = - 18
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- 3 = 2 + ( subtract 2 from both sides )
- 5 = ( multiply both sides by 3 to clear the fraction )
- 15 = x
