It's hard to type and hard to read the "inverse tangent" function, as you've seen (above).
So, use "arctan x" instead.
Then the problem becomes: "differentiate cos (arctan x)."
You must apply first the rule for differentiating the cosine function, and next apply the rule for differentiating the arctan function:
(d/dx) cos (arctan x) = - sin (arctan x) * [1/(1+x^2)]
Answer:
√7 ≈ 2.646
Step-by-step explanation:
The law of cosines is applicable. It tells you ...
c² = a² + b² - 2ab·cos(C) . . . . . where a, b, c are triangle side lengths, and angle C is opposite side c.
Filling in the given information, you have ...
c² = 2² + 3² - 2·2·3·cos(60°) = 4 + 9 - 12·(1/2) = 7
c = √7 ≈ 2.646
The length of the third side is √7, about 2.646 units.
How many three-fourths are in 2? 2 complete sets of three-fourths can be made and 2 of the 3 pieces need to make \frac34 are left over, so we have another \frac23 of a three-fourths. and we can see that there are 2 wholes with 4 fourths in each whole, so there are 2\times 4 fourths in 2.