किसी स. श्रे. यदि `a=1, a_(n)=20` और `S_(n)=399` हो, तो n बराबर है

In an AP, if a = 1 , a_(n)= 20 and S_(n) = 399 , then n is equal to

In an A.P., if a = 1 , a_(n) = 20 and S_(n) = 399 , then n = ……..

In an AP, if a = 1 , a_(n)= 20 and S_(n) = 399 , then n is equal to

If tanA=n tan B and sinA=m sin B, then the value of cos^2 A is यदि tanA=n tan B और sinA=m sin B, तो cos^2 A का मान है

If 20% of a = b, then b% of 20 is equal to: यदि a का 20% =b है, तो 20 का b% किसके बराबर होगा ?

The sum of an A.P. is 1 and the nth term is 20. If S_(n)=399 , then n=…..