4+(10/5)=6
6-2=4
The two aides aren't equal.
Cos 157.5º=-cos (180º-157.5º)=-cos 22.5=-cos(45/2)
cos Ф/2=⁺₋√((1+cosФ)/2).
In this case 157.5º is in the second quadrant, therefore we use the following equation:
cos Ф/2=-√((1+cosФ)/2). (we will have a negative number)
cos 157.5º=-cos (45/2)=-√((1+cos 45º)/2)
=-√((1+√2/2)/2)
=-√((2+√2)/4)
=-√(2+√2) / 2 (≈-0.92387...)
Answer: cos 157.5º= -√(2+√2) / 2
Answer:
Step-by-step explanation:
You;ll run into this formula a lot. Make sure you study it carefully.
A = 25
a = 5
d = 13
Find n
25 = 5 + 13*(n- 1)
20 = 13(n - 1)
This isn't going to work out. 20/13 does not give a whole number which it should.
9514 1404 393
Answer:
18
Step-by-step explanation:
90 = 18·5
126 = 18·7
180 = 18·10
990 = 18·55
The greatest common factor of these numbers is 18.
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<em>Comment on the GCF</em>
It can be useful to know Euclid's algorithm for finding the GCF:
- Determine the remainder from dividing the larger number by the smaller.
- If the remainder is zero, the smaller number is the GCF. If the remainder is non-zero, use it to replace the larger number and repeat from step 1.
For example, 126 mod 90 = 36; 90 mod 36 = 18; 36 mod 18 = 0, so 18 is the GCF of 126 and 90. (The modulo function 'mod' returns the remainder from division.)
