Question
Alisha had Rs. 7500 with her. She invested 20% of the
sum at 7% p.a. and the rest at 13% p.a., both at simple interest for 6 years each. Find the total interest received by Alisha.Solution
ATQ, Interest received by Alisha at 20% of the sum = (0.20×7500×7×6)/100=Rs.630 Interest received by Alisha on 80% of the sum = (0.80×7500×13×6)/100=Rs.4680 Therefore, total interest received = 630 + 4680 = Rs. 5310
If 6sin²x + 2cos²x − 3 = 0, then find the value of sinx, given that 0° < x < 90°.

If tan 4θ = cot 14θ, then find the value of cos 9θ.
- If sin(A + B) = 1/2 and cos(A + 2B) = 1/√2, where 0° < A, B < 90°, then find the value of tan(2A).
- Find the maximum value of (12sin A + 16cos A).
If sec 4A = cosec (3A - 50°), where 4A and 3A are acute angles, find the value of A + 75.
If sec x + tan x = 11 then find secx?
If sec A + tan A = 7 and sec A - tan A = (1/7), find the value of cos A.