Answer: 0.4693877
Step-by-step explanation:
Given that:
cos x=−6/7,
From trigonometry :
Cosx + sinx = 1
Cos2x = cos(x + x)
Recall the double angle identity:
Cos2x = 2cos^2x - 1
Sin2x = 1 - 2sin^2x
Since cosx = - 6/7
Then
Cos2x = 2cos^2x - 1
Cos2x = 2cosx^2 - 1
Cos2x = 2(-6/7)^2 - 1
Cos2x = 2(36/49) - 1
Cos2x = 2 * (72/98) - 1
Cos2x = (2 * 0.7346938) - 1
Cos 2x = ( 1.4693877 - 1)
Cos2x = 0.4693877
2➗5 for a division problem and for a fraction it is 2/5
Answer:

Try to solve the similtanious equation to find the first term and the common difference, then use that information to figure out the 80th term... Update me if you need further help ...
<span>The integral of (x^2 + 6x)dx is 1/3x^3 + 3x^2 + c.
Because this is not an integration with specific bounds, you must include a constant at the end.
In general, to integrate, add 1 to the exponent of x and then whatever number is the exponent of x, divided the number in front of x by that.</span>
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Answer:
42 feet
Step-by-step explanation:
First let know what is
Yards to Feet
Note that;
1 Yard ⇒ 3 Feet
Thus, Formula: Multiply the length value by 3
Given:
Lena bought 14 yards of ribbon. How many feet of ribbon did she buy?
Therefore, 14 * 3 = 42
Hence, Answer is Lena brough 42 feet of ribbon.
~[CloudBreeze]~