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I'll do the first one.....see if you can do the second

1.   

First term  = 2(3) - 10  =  - 4

Last term = 2(6) - 10 = 12

Sum   = ( first term + last term) * (number of terms)  / 2   = (-4 + 12) (6 - 3 + 1) /2  =

(-4 + 12) (4) /2  =

8 ( 4) / 2 =

32 / 2  =

16

Second one

First term =  2(1)^2 - 4  =  -2

Last term = 2(4)^2 - 4  =  32 - 4  =  28

Number of terms  =  4

1 - listfor(k, 3, 6, (2*k - 10)) =(-4, -2, 0, 2) = - 4

2 - listfor(k, 1, 4, (2*k^2 - 4)) = (-2, 4, 14, 28) = 44