Solve it by reduction method (pivotal method)

On a straight line passing through the foot of a tower, two points A and D are at a distance of 4 metre and 16 metre from the food respectively if the angle of elevation of c and d from the top of the tower of complementary then find the height of the tower

1/16a

Two dairy owner

I didnt get how to do all questions...

Why can't we simply differentiate it? 

 please explain it step by step 

Abcd is trapezium  in  which  ab is  parallel  to DC  DC  is  produced to e such that ce is equal to ab prove that ARea of triangle abd is equal to area of triangle bce

Limit 0 to 1 integration [log(1+x)]/(1+x^2)

limit x tends to 0 2e to the power x-2/x

payroll in tally

2+x/2+x

 

 

 

 

 

 

 

 

What is bisected 

What is recipets and payment account

Rajinder and surinder are partners in a firm sharing profit in the ratio 4:1on april15,2015,they admit narender as a new partner. On that date there was a balance of 20,000 in general reserve and a debit balance of 10,000 in the profit and loss account of the firm. On that date the firm had also a joint life policy for 30,000 (surrender value of 15,000).pass necessary journal entries

(2+underroot3)^x2-3x +(2-underroot3)^x2-3x=2