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2 years ago

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Clock wise angle from minutes hand to hour hand at 7 o'clock is what (a)240° (b)230° (c)220° (d)210° (e)200°

2 answers:

AlladinOne [14]2 years ago

7 0

Answer:

Option D) Angle at 7 o'clock = 210 degrees

Step-by-step explanation:

The whole clock = 360 degrees

Every 1 hour = 360/12

Every 1 hour = 30 degrees

Angle at 7 o'clock = 30*7

Angle at 7 o'clock = 210 degrees

lord [1]2 years ago

6 0

Answer:

d

Step-by-step explanation:

At 7 o' clock the minute hand is at 12 and the hour hand at 7

There is 360° in a complete revolution, thus between 7 and 12

angle = $\frac{7}{12}$ × 360° = 7 × 30° = 210° → d

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$\boxed{y(x)=C_1e^x\cos\dfrac{\sqrt3}2x+C_2e^x\sin\dfrac{\sqrt3}2x+\sin x}$

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Assume a solution of the form

$y_p=e^x(a\sin x+b\cos x)$

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Substituting into the ODE gives

$2e^x(a\cos x-b\sin x)-3e^x((a+b)\cos x+(a-b)\sin x)+2e^x(a\sin x+b\cos x)=e^x\sin x$

$-e^x((a+b)\cos x+(a-b)\sin x)=e^x\sin x$

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