If a,b,c are in Harmonic Progression Prove that 1/(b-a) + 1/(b-c) = 1/a + 1/c

Hey everyone, looking for some more help / advice :) Questions first, my answers at the bottom :) Question One The value of a machine which costs £35000 depreciates by 10% per annum. A) What is its value after 10 years? The costs of repairs and maintenance is £2000 in the first year and...

Find the number of terms which is common to two arithmetic progressions: 3,7,11,. 407 and 2,9,16,. 709.

1.the seven th term of an A.P is 32 and its 13 term is 62 find AP.(arithmetic progression) 2.find the sum of 1 st 25 term of an ap whose n th term is given by tn = 2-3n 3.the 7 th term of an AP is 20 and its 13 th term is 32 find the AP. 4.the 8 th term of an AP is 37 and 12 th term...

if you put $1 in your piggy bank at the start of a year, another $2 the second day, another $3 the third day, and continue saving this way for a year, what will be the sum at the end of a year of 365 days