`(a+1/a+2)^2=4` then find `a^2+1/a^2` given that `a^2+1/a^2` can not be negative

If a- (1)/(a) = 4 , find : a^2 + (1)/(a^2)

If a - 1/a = 4 , find the value of a^2 + 1/a^2

If a + (1)/(a) = 2, find (a^(4) + 1)/(a^(2))

If A = [(1,2),(2,4)] , find A^-1

2.Find the difference (a) 1/2-1/4

Find the value of   4 ÷ 1/2 - 1/2 ÷ 2 + 1/2 ( 2 + 1/2 )

Read the following and answer the questions given below. 1,2,3,4….are natural numbers or counting numbers. The sum of first 4 numbers is 1+2+3+4=(1+4)+(2+3) = 5+5 = 5xx2 =(4+1)+4/2 We can make pairs as given above and can establish a formula to find the sum of first n natural numbers as sum = (1+n)xxn/2 Find the sum of first 10 natural numbers.

If 1/1^2+1/2^2+1/3^2+.... upto infty=pi^2/6 , then, find 1-1/2^2+1/3^2-1/4^2+....upt o infty .

If A=[1 2 2 2 1 2 2 2 1] , find A^(-1) and prove that A^2-4A-5I=O .