Sin² x + sin x cos x = 0
sin x ( sin x + cos x ) = 0
sin x = 0 ; x 1 = k π ; k ∈ Z
sin x + cos x = 0 / ²
sin² x + 2 sin x cos x + cos² x = 0
2 sin x cos x + 1 =0
sin ( 2 x ) = - 1
x = 3π / 2 + 2 kπ / : 2
x 2 = 3π / 4 + kπ ; k ∈ Z
Answer:400
Step-by-step explanation: if everyone hand shakes every other person the answer will be 400, because 20 times 20 is 400
hope I helped.
If you add 5x to 2x+2 you will get 7x+2. You would set this equation equal to 80, so it would be 7x+2=80. When you solve this you will get 11.1428571429, which can be rounded to 11, 11.1, or 11.14, whichever you prefer.
The second term of the arithmetic sequence is:
a₂= -9
<h3>
How to find the second term in the sequence?</h3>
Here we have an arithmetic sequence, such the the recursive formula is:
aₙ = aₙ₋₁ + 4
So to get each term, we need to add 4 to the previous one.
We know that the first term is:
a₁ = -13
Then the second term will be:
a₂ = a₁ + 4 = -13 + 4 = -9
Learn more about arithmetic sequences:
brainly.com/question/6561461
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Answer: B and D
Step-by-step explanation:
B=-2
D=2
The negative and positive signs cancel out, leaving you with zero.
Ex: you take two steps back, but then you take two steps forward so you're back where you started (0).
