4a is the answer I believe you’re looking for
Answer:
See Below.
Step-by-step explanation:
We want to verify the identity:

Note that the left-hand side is a perfect square trinomial pattern. Namely:

If we let <em>a</em> = csc(x) and <em>b</em> = cot(x), we can factor it as such:

Let csc(x) = 1 / sin(x) and cot(x) = cos(x) / sin(x):

Combine fractions:

Square (but do not simplify yet):

Now, we can make a substitution. Let <em>u</em> = <em>x</em> / 2. So, <em>x</em> = 2<em>u</em>. Substitute:

Recall that cos(2u) = 1 - sin²(u). Hence:

Simplify:

Recall that sin(2u) = 2sin(u)cos(u). Hence:

Square:

Cancel:

Since sin(u) / cos(u) = tan(u):

We can substitute <em>u</em> back for <em>x</em> / 2:

Hence proven.
<span>2cos^2x = sin2x
2cos^2x = 2sin x cos x
(2sin x cos x) / (2cos^2x) = 1
sin x / cos x = 1
tan x = 1
x = π/4</span>
Answer: D+Q= 30
0.10 d+ 0.25 q= 4.80
Step-by-step explanation:
A dime is worth 10 cents and a quarter is worth 25 cents.