First term: a1 = 151
common difference: d = -14 (we decrease by 14 each time, eg, 151-14 = 137)
nth term of this arithmetic sequence is...
an = a1+d(n-1)
an = 151+(-14)(n-1)
an = 151-14n+14
an = -14n+165
This will be used in the formula below
Sn = n*(a1+an)/2
<span>Sn = n*(151+(-14n+165))/2
</span><span>S26 = 26*(151+(-14*26+165))/2 ... replace every n with 26
</span>S26 = -624
The final answer here is choice C) -624
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Answer:
how r we supposed to help if u dont have the picture
Step-by-step explanation:
Answer: x=3
Step-by-step explanation: Subtract 6 from both sides, Simplify
15−6 to 9, and then divide both sides by three.
3x=15−6
3x=9
x=9/3
x=3
Hope this helps, have a BLESSED day! ☺️
Answer:
D
Step-by-step explanation:
Hello,
y=sin²(cos(2x))
y'=2*sin(cos(2x))*cos(cos(2x))*(-sin(2x)*2)
= -4*sin(cos(2x))*cos(cos(2x))*sin(2x)