(tan(<em>x</em>) + cot(<em>x</em>)) / (tan(<em>x</em>) - cot(<em>x</em>)) = (tan²(<em>x</em>) + 1) / (tan²(<em>x</em>) - 1)
… = (sin²(<em>x</em>) + cos²(<em>x</em>)) / (sin²(<em>x</em>) - cos²(<em>x</em>))
… = -1/cos(2<em>x</em>)
Then as <em>x</em> approaches <em>π</em>/2, the limit is -1/cos(2•<em>π</em>/2) = -sec(<em>π</em>) = 1.
It depends on how you count them. If you describe them by their dimensions, lowest one first, you can have
1 x 1 x 18
1 x 2 x 9
1 x 3 x 6
2 x 3 x 3
Of course, these dimensions can be put in any order.
The nth term is 6n+4 and the 40th term is 244
Answer:
a
Step-by-step explanation:
