Direct Ratio MCQ Quiz in मल्याळम - Objective Question with Answer for Direct Ratio - സൗജന്യ PDF ഡൗൺലോഡ് ചെയ്യുക
Last updated on Mar 16, 2025
Latest Direct Ratio MCQ Objective Questions
Top Direct Ratio MCQ Objective Questions
Direct Ratio Question 1:
If \(\rm tan A = {3 \over 8},\) then the value of \({3 \sin A + 2 \cos A} \over 3 \sin A - 2 \cos A\) is:
Answer (Detailed Solution Below)
Direct Ratio Question 1 Detailed Solution
Given:
\(\rm tan A = {3 \over 8},\)
Concept used:
TanA = SinA / CosA
Calculation:
\({3 \sin A + 2 \cos A} \over 3 \sin A - 2 \cos A\)
Dividing by CosA we get,
3 TanA + 2 / 3 TanA - 2
Now putting the value of Tan A we get,
⇒ \( (3 × {3\over8}+ 2)\over (3 × {3\over8}- 2)\)
⇒ \(- {25 \over7}\)
∴ The correct option is 2
Direct Ratio Question 2:
If acot θ = b, then what will be the value of \(\frac{bcosθ - asinθ}{bcosθ + asinθ}\)?
Answer (Detailed Solution Below)
Direct Ratio Question 2 Detailed Solution
Given
a cot θ = b
Calculation
\(\frac{bcosθ - asinθ}{bcosθ + asinθ}\)
Dividing the whole equation by cosθ, we get:
⇒ (b - asinθ/cosθ)/(b + asinθ/cosθ)
⇒ (b - atanθ)/(b + atanθ)
⇒ (b - a × a/b)/(b + a × a/b)
⇒ (b2 - a2)/(b2 + a2)
The value of the expression is (b2 - a2)/(b2 + a2) .
Direct Ratio Question 3:
If tan x = \(\frac{7}{5}\), then the value of \(\frac{9 \sin x - \frac{42}{5}\cos x}{15 \sin x + 21 \cos x}\) is:
Answer (Detailed Solution Below)
Direct Ratio Question 3 Detailed Solution
Given
tan x = 7/5
Formula used
tan x = P/B
sin x = P/H
cos x = B/H
Calculation
tan x = 7/5 = P/B
H2 = P2 + B2
H2 = 72 + 52
H2 = 49 + 25 = 74
h = √74.
\(\frac{9 \sin x - \frac{42}{5}\cos x}{15 \sin x + 21 \cos x}\)
⇒ (9 × 7/√74 - 42/5 × 5/√74)/(15 × 7/√74 + 21 × 5/√74)
⇒ (21/√74)/(210/√74)
⇒ 21/210
⇒ 0.1
The value is 0.1
Direct Ratio Question 4:
If Cos A = \({{9} \over 41}\), find cot A.
Answer (Detailed Solution Below)
Direct Ratio Question 4 Detailed Solution
Given:
Cos A = 9/41
Formula used:
cot A = cos A/sin A
Cos2 A + sin2 A = 1
Calculation:
Cos2 A + sin2 A = 1
⇒ ( 9/41)2 + sin2 A = 1
⇒ sin2 A = 1 - 81/1681
⇒ sin2 A = 1600/1681
⇒ sin A = 40/41
⇒ cot A = cos A/sin A
⇒ cot A = 9/40
∴ Option 1 is the correct answer.
Direct Ratio Question 5:
If cotθ = 4/3, then evaluate: (secθ(1 + cot2θ)(cosec2θ - cot2θ)) / cosec3θ.
Answer (Detailed Solution Below)
Direct Ratio Question 5 Detailed Solution
Calculation:
cosec2θ - cot2θ = 1,
cosec2θ = 1 + cot2θ
So,
(secθ(1 + cot2θ)(cosec2θ - cot2θ)) / cosec3θ
⇒ (sec θ × cosec2θ × 1) / cosec3θ
⇒ (sec θ) / (cosec θ)
⇒ (1/cos θ) / (1/sinθ)
⇒ sinθ / cosθ
⇒ tan θ = 1/cot θ = 1/(4/3) = 3/4
∴ The corrct answer is option (1).
Direct Ratio Question 6:
If sin θ = \(1 \over 2\), then the value of (3cos θ - 4 cos3 θ) is:
Answer (Detailed Solution Below)
Direct Ratio Question 6 Detailed Solution
Given:
sin θ = \(1 \over 2\)
Concept used:
Calculation:
sin θ = \(1 \over 2\)
⇒ sinθ = sin 30°
So, θ = 30°
3cos θ - 4 cos3 θ
⇒ 3 × \(\sqrt3 \over 2\) - 4 × \(3\sqrt3 \over 8\)
⇒ \({3\sqrt3 \over 2} - \frac{3\sqrt3}{2}\)
⇒ 0
∴ The required answer is 0.
Direct Ratio Question 7:
If tan α = 6, then sec α equals to:
Answer (Detailed Solution Below)
Direct Ratio Question 7 Detailed Solution
Given:
Tan α = 6
Concept used:
Tan θ = P/B
Sec θ = H/B
Where, P = perpendicular; B = base; H = hypotenuse
Formula used:
Pythagorean theorem:
H2 = P2 + B2
Where, P = perpendicular; B = base; H = hypotenuse
Calculation:
Tan α = 6/1 = P/B
Using Pythagorean theorem:
⇒ H2 = P2 + B2
⇒ H2 = (6)2 + (1)2
⇒ H = √37
Sec α = H/B = √37
∴ The correct answer is √37.
Direct Ratio Question 8:
If 4 tan θ = 3, then \(\frac{4 \sin θ-\cos θ+1}{4 \sin θ+\cos θ-1}=\) _________.
Answer (Detailed Solution Below)
Direct Ratio Question 8 Detailed Solution
Given:
4 tan θ = 3
Calculation:
Applying Pythagoras Theorem
AC2 = AB2 + BC2
AC2 = 32 + 42
AC = 5
sinθ = 3/5
cosθ =4/5
\(\frac{4 \sin θ-\cos θ+1}{4 \sin θ+\cos θ-1}\)
Put the above values
⇒ \(\frac{4 \times 3/5-4/5+1}{4 \times 3/5+4/5-1}\)
⇒ \(\frac{12/5-4/5+1}{12/5+4/5-1}\) = \(\frac{(12-4+5)/5}{(12 +4 - 5)/5}\)
⇒ \(\frac{13/5}{11/5}\) = \(\frac{13}{11}\)
∴ Option 4 is the correct answer.
Direct Ratio Question 9:
If 7 tan θ = 3, and θ is an acute angle, then \(\frac{5 \sin \theta - \cos \theta}{5 \sin \theta + 2 \cos \theta}\) is equal to:
Answer (Detailed Solution Below)
Direct Ratio Question 9 Detailed Solution
Given:
7tan θ = 3
Calculation:
\(\frac{5 \sin \theta - \cos \theta}{5 \sin \theta + 2 \cos \theta}\)
Divide by 'cos θ' in both numerator and denominator,
⇒ \(\frac{5 (\sin \theta/ \cos \theta) -1}{5 (\sin \theta/ \cos \theta) + 2 }\)
⇒ \(\frac{5\ tan \theta -1}{5 \ tan \theta + 2 }\)
⇒ [5 × 3/7 - 1] / [5 × 3/7 + 2]
⇒ [15/7 - 1] / [15/7 + 2]
⇒ [(15 - 7)/7] / [(15 + 14)/7]
⇒ [8/7] / [29/7]
⇒ 8/29
∴ The correct answer is option (1).
Direct Ratio Question 10:
If sin x = \(\frac{3}{10}\), then what is the value of tan x + cot x = ?
Answer (Detailed Solution Below)
Direct Ratio Question 10 Detailed Solution
sin x = (3/10)
Formula used:-
1 + tan2x = sec2x
secx = 1/cosx
tan x = sin x/cos x
Calculation:-
⇒ tanx + cotx
⇒ tanx + 1/tanx
⇒ (1 + tan2x )/tanx
⇒ sec2x /tanx
⇒ 1/sinx cosx [cosx = (√100 - 9)/10]
⇒ 1/(3/10)(√91/10) = 100/3√91
∴ The required answer is 100/3√ 91.