Question

I need to show all the steps CLEARLY ,so please I want a nice answer take your time and answer properly​

Answer 1

Step-by-step explanation:

Please say which publication it is.....

If ML Aggarwal,Arya Publication

then,download ICSE 8th class solution

If Foundation Maths then, you can see website of this book in Google.....

Please follow me and mark me as Brainlist!!!

Answer 2

Answer:

20. 2 x 3 ^n + 1 + 7 x 3^n – 1 / 3^n + 2 – 2(1/3)^1- n

We can write this as  

2 x 3^n x 3^1 + 7 x 3^n x 3^-1 / 3^n + 2 – 2 x (3^-1)^1-n

Taking 3^n as common factor we get

3^n(2 x 3 + 7 x 3^-1) /3^n+2 – 2 x 3^n-1

3^n(2 x 3 + 7 x 3^-1)/ 3^n x 3^2 – 2 x 3^n x 3^-1

3^n(2 x 3 + 7 x 3^-1)/3^n(3^2 – 2 x 3^-1)

6 + 7/3 / 9 – 2/3

25/3 / 25/3

= 1