Hi, i'd really appreciate it if someone answere this :)

Mathematics

2 answers:

Vesna [10]3 years ago

8 0

Answer:

Step-by-step explanation:

12 number

Wherever you see an n put in 12

12 (12 + 1)/2

12 * 13 / 2

6 * 13

The 12th triangular number is 78

50th triangular number

Again, wherever you see an n put in 50

n/2 * (n+ 1)

50/2 * (50 + 1)

25 * 51

1275

m_a_m_a [10]3 years ago

6 0

Answer:

12th triangular number is 78

50th triangular number is 1275

Step-by-step explanation:

12+1=13

12÷2=6

6x13=78

if you do this for 50 you get 1275

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Cos^2 x+4sin^2 x/2=1

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