Question
 If f(x) = 3x² − 7x + 5, find f(2a) −
4f(a).Solution
ATQ,
f(2a) = 3(4a²) − 14a + 5 = 12a² − 14a + 5 f(a) = 3a² − 7a + 5 f(2a) − 4f(a) = (12a² − 14a + 5) − (12a² − 28a + 20) = 14a − 15
An equal sum of money is invested in two schemes which offer interest at the same rate but one at simple interest and the other at compound interest (co...
B invested Rs. 8000 in a compound interest scheme for 2 years at an annual interest rate of x%. If he received Rs. 3520 as interest, find the rate of in...
A man deposited Rs. 8500 in a bank offering compound interest of 20% p.a. compounded annually for first 2.5 years and after that simple interest of 25% ...
A man invested Rs.Y in a scheme S at 14% rate of simple interest for 7 years. After 7 years, he reinvested the amount received from the scheme S at same...
A certain sum amounts to Rs. 2400 in 4 years and to Rs. 3456 in 6 years, when invested at R% p.a. compound interest, compounded annually. Find the amoun...
- A sum of money grows to Rs. 2,800 in 3 years and Rs. 3,280 in 5 years under simple interest. What is the original principal amount?
The difference between compound interest and simple interest on a sum of Rs. 20,000 for 2 years at the same rate is Rs. 200. What is the annual rate of ...
- A person invested Rs. 30,000 in two schemes. One scheme gives a simple interest of 7% p.a., while the other scheme gives 11% p.a. If the total interest ear...
A man deposited Rs. ‘x + 1200’ at 12% per annum simple interest and earned Rs. 528 as interest after 2 years. Find the interest earned by him if he ...
Arjun made two investments: the first was Rs. 1,600 at an annual simple interest rate of R% for a period of 2 years, and the second was Rs. 2,000 at an ...
