Is `1^2` equal to `2^1`? Justify.

Is 3^2 equal to 2^3 ? Justify.

If the sum (3)/(1^(2)) + (5)/(1^(2) + 2^(2)) + (7)/(1^(2) + 2^(2) + 3^(2)) + …+ upto 20 terms is equal to (k)/(21) , then k is equal to

2tan^(-1)(-2) equal to

Can you find the HCF of 1.2 and 0.12? Justify your answer.

f: R to R defined by f(x)=(2x+1)/(3) , then this function is injection or not? Justify.

State whether the following statements are true or false. Justify your answer S = {1, 2, 3} implies 5 in S .

LetA(4,2),B(6,5)andC(1,4)betheverticesof DeltaABC . What do you observe ? Justify the point that divides each median in the ratio. 2:1 is the centroid of a triangle.