[" What is the value of the following expression? "],[(1)/((2^(2)-1))+(1)/((4^(2)-1))+(1)/((6^(2)-1))+cdots+(1)/((20^(2)-1))]

What is the value of the following expression? (1)/((2^(2)-1))+(1)/((4^(2)-1))+(1)/((6^(2)-1))+backslash+(1)/((20^(2)-1))(9)/(19) (b) (10)/(19)(c)(10)/(21) (d) (11)/(21)

What is the maximum value of the expression 1/(x^2 + 5x + 10) ?

The value of the expression

What is the value of the expression 100 + bar(500-10) -80 ?