Q. Solve the equation(2sinx−1)(2cosx+1)=0 within the interval −180≤x≤180,
Set Factors to Zero: First, we set each factor in the equation to zero because if the product of two factors is zero, at least one of the factors must be zero.So, we have 2sinx−1=0 and 2cosx+1=0.
Solve First Equation: Now, let's solve the first equation: 2sinx−1=0. Add 1 to both sides to isolate the term with \ ext{sin} x: 2sinx=1.
Find Angles for sinx: Next, divide both sides by 2 to solve for sinx: sinx=21.
Solve Second Equation: We look for angles where the sine is 21. These are x=30 degrees and x=150 degrees.
Find Angles for cosx: Now, let's solve the second equation: 2cosx+1=0. Subtract 1 from both sides to isolate the term with cosx: 2cosx=−1.
Find Angles for cosx: Now, let's solve the second equation: 2cosx+1=0. Subtract 1 from both sides to isolate the term with cosx: 2cosx=−1. Then, divide both sides by 2 to solve for cosx: cosx=−21.
Find Angles for cosx: Now, let's solve the second equation: 2cosx+1=0. Subtract 1 from both sides to isolate the term with cosx: 2cosx=−1. Then, divide both sides by 2 to solve for cosx: cosx=−21. We look for angles where the cosine is −21. These are x=−120 degrees and 2cosx+1=00 degrees.