From the given figure, the value of cos y is : 1. 1/3 2. 1/4 3. 12/13 4. 1(1/12)

In Δ ABC, ⇒ AC2 = AB2 \+ BC2 (∵ AC is hypotenuse) ⇒ AC2 = 42 + 32 ⇒ AC2 = 16 + 9 ⇒ AC2 = 25 ⇒ AC = ⇒ AC = 5 In Δ ADC, ⇒ DC2 = AC2 \+ DA2 (∵ DC is hypotenuse) ⇒ DC2 = 52 \+ 122 ⇒ DC2 = 25 \+ 144 ⇒ DC2 = 169 ⇒ DC = ⇒ DC = 13 cos y = Hence, option 3 is the correct option.

Mathematics

From the given figure, the value of cos y is :
$\dfrac{1}{3}$
$\dfrac{1}{4}$
$\dfrac{12}{13}$
$1\dfrac{1}{12}$

Trigonometric Identities

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Answer

In Δ ABC,

From the given figure, the value of cos y is : Trigonometrical Ratios, Concise Mathematics Solutions ICSE Class 9.

⇒ AC² = AB² + BC² (∵ AC is hypotenuse)

⇒ AC² = 4² + 3²

⇒ AC² = 16 + 9

⇒ AC² = 25

⇒ AC = $\sqrt{25}$

⇒ AC = 5

In Δ ADC,

⇒ DC² = AC² + DA² (∵ DC is hypotenuse)

⇒ DC² = 5² + 12²

⇒ DC² = 25 + 144

⇒ DC² = 169

⇒ DC = $\sqrt{169}$

⇒ DC = 13

cos y = $\dfrac{Base}{Hypotenuse}$

$= \dfrac{DA}{DC}\\[1em] = \dfrac{12}{13}$

Hence, option 3 is the correct option.

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Mathematics

From the given figure, the value of cos y is :
$\dfrac{1}{3}$
$\dfrac{1}{4}$
$\dfrac{12}{13}$
$1\dfrac{1}{12}$

Trigonometric Identities

Answer

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Mathematics

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Trigonometric Identities

Answer

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From the given figure, the value of cos y is :
$\dfrac{1}{3}$
$\dfrac{1}{4}$
$\dfrac{12}{13}$
$1\dfrac{1}{12}$

ABCD is a rhombus with diagonals BD and AC equal to 12 cm and 16 cm respectively. The value of cosec x is :
$1\dfrac{2}{3}$
$3\dfrac{1}{3}$
$\dfrac{1}{2}$
$1\dfrac{1}{3}$

If sin A - cosec A = 2, the value of sin² A + cosec² A is :
2
0
4
6