Question

The rod AC of a TV disc antenna is fixed
at right angles to the wall AB and a rod
CD is supporting the disc as shown in
Fig. 4. If AC=1.5 m long and CD = 3 m,
find (i) tan (ii) sec 0 + cosec e.
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Answer 1

tantheta=1.5/AB

an=1.5*tan theta

Answer 2

The rod AC of a TV disc antenna is fixed  at right angles to the wall AB and a rod  CD is supporting the disc.

Given

AC = 1.5 m

CD = 3 m

from given figure, we have,

CD² = AD² + AC²

⇒ AD² = CD² - AC²

= 3² - 1.5² = 6.75

CD = 2.59 m

(i) tan

To find: tan 0

tan 0 = AC/AD

= 1.5/2.59

∴ tan 0 = 0.579

(ii) sec 0 + cosec e

To find: sec 0 + cosec 0

= CD/AD + CD/AC

= 3/2.59 + 3/1.5

∴ sec 0 + cosec 0 = 3.158