Step-by-step explanation:
We must prove that
cos²a(csc²a-cot²a) = cos²a
If we look at both sides, we can see that we have cos²a * something = cos²a. Therefore, if we can get that something to equal 1, we have our proof. In this case, that something is csc²a-cot²a. Using this information, we can work from within the parenthesis and go from there.
We can start by expanding the items in the parenthesis. Taking that csc(x) = 1/sin(x) and cot(a) = cos(x)/sin(x), we can say that
cos²a(csc²a-cot²a) = cos²a(1/sin²a - cos²a/sin²a). Because both items in the parenthesis have a denominator of sin²a, we can subtract cos²a from 1 to get
cos²a(1/sin²a - cos²a/sin²a)= cos²a((1-cos²a)/sin²a))
Next, we know that cos²a+sin²a=1, so 1-cos²a = sin²a. Plugging that in, we get
cos²a((1-cos²a)/sin²a)) = cos²a(sin²a/sin²a)
= cos²a(1)
= cos²a
The answer is C because there is no number raised to the power of x in the equation
The answers are A and E.
The factors are (2x +9)(2x-9). If you solve each one by equaling each one to zero. You will get:
2x+9=0 2x-9=0
x=-9/2 x=9/2
I don't understand the y after the 4... but would it be x=2 y=1 ?
35/80 in simplest form.
So, we need to divide 35 and 80 by 5, because they are both divisible by 5.
35 ÷ 5 = 7
80 ÷ 5 = 16.
7/16 cannot be simplified.
So, →7/16← is your answer.
Glad I could help, and good luck!
AnonymousGiantsFan
