C; the first and last letters in each group is connected, after U and V being first and last it should be W and X being first and last.
Answer:
see explanation
Step-by-step explanation:
Using the trigonometric identity
• 1 + cot²x = csc²x
Consider the left side
x -
x
Factorise as a difference of squares
= (csc²x - cot²x)(csc²x + cot²x)
= (1 + cot²x - cot²x)(csc²x + cot²x)
= csc²x + cot²x
= csc²x + csc²x - 1
= 2csc²x - 1 = right side ⇒ verified
A function is "a expression or equation involving one or more variables".
For example:
(x² + 7a) is a function.
hope this helps