NIMCET 2011 — Mathematics PYQ
NIMCET | Mathematics | 2011The general solution of 3cosx+sinx=3 is:
Choose the correct answer:
- A.
2nπ±6π
- B.
2nπ±3π
no solution
Explanation
1. Identify the form:
The expression is in the form acosx+bsinx, where a=3 and b=1.
2. Find the range of the expression:
The maximum and minimum values of acosx+bsinx are given by ±a2+b2.
3. Compare with the given equation:
The given equation is:
However, as calculated above, the maximum value that 3cosx+sinx can ever reach is 2.
4. Logical Conclusion:
Since 2 < 3, the expression 3cosx+sinx can never equal 3 for any real value of x.
Conclusion:
There is no real solution for this equation.
The correct option is (c).
Explanation
1. Identify the form:
The expression is in the form acosx+bsinx, where a=3 and b=1.
2. Find the range of the expression:
The maximum and minimum values of acosx+bsinx are given by ±a2+b2.
3. Compare with the given equation:
The given equation is:
However, as calculated above, the maximum value that 3cosx+sinx can ever reach is 2.
4. Logical Conclusion:
Since 2 < 3, the expression 3cosx+sinx can never equal 3 for any real value of x.
Conclusion:
There is no real solution for this equation.
The correct option is (c).
