Evaluate `|[1/(a+1),1/(a+2),1/(a+3)],[1/(a+2),1/(a+3),1/(a+4)],[1/(a+3),1/(a+4),1/(a+5)]|`

Evaluate det[[(1)/(a+1),(1)/(a+2),(1)/(a+3)(1)/(a+2),(1)/(a+3),(1)/(a+4)(1)/(a+3),(1)/(a+4),(1)/(a+5)]]

Find value of determinant of A =abs[[(a+1)(a+2),(a+2),1],[(a+3)(a+2),(a+3),1],[(a+3)(a+4),(a+4),1]]

Evaluate (1) 2^(-3) (2)(-4)^(-2) (3)1/3^(-2) (4)(1/2)^(-5)

[4(1)/(5)-:{1(3)/(4)-(1)/(2)(3(1)/(2)-(1)/(4)-(1)/(6))}]

Evaluate the following: ([(1,3),( -1,-4))]+[(3 ,-2 ),(-1 ,1)]) [(1 ,3,5),( 2 ,4 ,6)]

If A=[[0,1,3],[1,2,x],[2,3,1]] and A^(-1)=[[(1)/(2),-4,(5)/(2)],[-(1)/(2),3,-(3)/(2)],[(1)/(2),y,(1)/(2)]] . Find x,y

Evaluate (-1)/3 xx (1/2+1/4)xx((-1)/3 xx 1/2)+((-1)/3 xx 1/4)

(1/(1!) +1/(2!) +1/(3!) + .....oo) (1/(2!) -1/(3!) +1/(4!)-1/(5!) .....oo)