Answer:
Step-by-step explanation: 2cos3 theta=1. Cos 3theta=1/2. Since cos 60°= 1/2. Therefore cos 3theta=cos 60°. Theta=20°.
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Answer:
3.183.10^7
Step-by-step explanation:
Amount Watch normally costs is w
Amount of the discount is 0.3w
Percent of decrease of the discount, as a decimal is 0.3
Percent of the normal cost that Chad paid, as a decimal is 0.7
Assume
Combining the fractions on the right hand side gives
The fractions will be equal as long as the their numerator are equal:
Polynomials are equal to one another if the coefficients of like terms are equal:
Solving this, you'd get and , so that your answer would be (26, -23).
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Instead of solving the system of equations above, there is a trick that involves picking so that some terms disappear and solving for either is much faster.
At the point where we have
notice that setting will eliminate . Doing so, we get
while setting would give