We will start off working on the right hand side.
<span>cot x - tan x </span>
<span>= [cos x / sin x] - [sin x / cos x] </span>
<span>= [(cos x)^ 2 - (sin x)^2] / [sin x cos x] </span>
<span>This is where it gets a bit tougher if you do not have your formula list with you. </span>
<span>(cos x)^ 2 - (sin x)^2 = cos(2x) </span>
<span>sin 2x = 2 sin x cos x </span>
<span>Note that by arranging the second formula, we will have sin x cos x = (1/2) sin 2x </span>
<span>Hence, we will get: </span>
<span>[(cos x)^ 2 - (sin x)^2] / [sin x cos x] </span>
<span>= [cos 2x] / (1/2)[sin 2x] </span>
<span>= 2[cos 2x] / [sin 2x] </span>
<span>= 2cot 2x </span>
There are 3,600 seconds in one hour so if it expands at rate of 930 miles per second then 930 * 3600= 3,348,000 miles per hour
The linear combination method is the same as the elimination method. Let's multiply the second equation by -2 so the x terms cancel each other out. When we do that we get a system of
and
. The x-terms cancel each other out giving us
and y = -3. Now sub -3 into one of the equations to solve for x. x+2(-3)=-4, and x - 6 = -4. x = 2. So the solution for our system is (2, -3)
4/22 and 8/44 are equivalent
Answer:
3/2 (decimals): 1.5
Step-by-step explanation:
1. 5(2d+4)=35 -> multiply 5 to (2d+4)
2. 10d + 20 = 35
3. Subtract 20 by both sides
10d = 35-20
10d = 15
4. divide 10 by both sides
d = 15/10
d = 3/2
