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If /A and /B are acute angles such th...

If `/_A` and `/_B` are acute angles such that `cos A=cos B` . then show that `/_A=/_B` .

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If A and B are positive acute angles and cos A = 1/7, cos B = 13/14 , then show that A-B=60^0 .

In a triangle A B C ,/_A B C=/_A C B and the bisectors of /_A B C and /_A C B intersect at O such that /_B O C=120^0dot Show that /_A=/_B=/_C=60^0

In a triangle A B C ,\ /_A B C=\ /_A C B and the bisectors of /_A B C\ a n d\ /_A C B intersect at O such that /_B O C=120^0dot Show that /_A=/_B=/_C=60^0 .

If ray O C stands on line A B such that /_A O C=/_C O B , then show that /_A O C=90^0

In Fig.9, if ray O C stands on line A B such that /_A O C=/_C O B , then show that /_A O C=90^0dot

ABC and DBC are two isosceles triangles on the same base BC (see Fig. 7.33). Show that /_A B D\ =/_A C D

In a /_\A B C , right angled at C and /_A=/_B , is cosA=cosB ?

Find acute angles A and B, if sin(A+B)=cos(A-B)=sqrt(3)/2 .

In A B C , if bisectors of /_A B C\ a n d\ /_A C B intersect at O at angle of 120^0 , then find the measure of /_A

If one of the angles A,B,C of a triangle is not acute, show that cos^2A+cos^2B+cos^2C=1

RD SHARMA ENGLISH-TRIGONOMETRIC RATIOS-All Questions
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  2. If cos e c\ A=2 , find the value of 1/(tanA)+(sinA)/(1+cosA)

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  3. If /A and /B are acute angles such that cos A=cos B . then show tha...

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  4. If angleA and angleP are acute angle such that tanA=tanP, then show th...

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  5. In a /\A B C , right angled at A , if tanC=sqrt(3) , find the valu...

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  6. State whether the following are true or false. Justify your answer. ...

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  7. State whether the following are true or false. Justify your answer. ...

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  8. Evaluate each of the following in the simplest form: sin60ocos30o+co...

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  9. Evaluate the following expressions: (i) 2sin^2 30^otan60^o-3cos^2 60...

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  10. Evaluate the following expressions: (i) 4cot^2 45o-sec^2 60^o + sin^...

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  11. Evaluate each of the following: (sin^2 45^o + cos^2 45^o)/(tan^2 60^...

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  12. Evaluate each of the following: (sin60^o)/(cos^2 45^o)-cot30^o + 15c...

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  13. Show that: 2(cos^2 45°+tan^2 60°)-6(sin^2 45°-tan^2 30°)=6 (ii) 2(...

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  14. Solve each of the following equations when 0^0 < theta<90^0 ...

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  15. Solve each of the following equations when 0 < theta<90 (i) 2sin^2t...

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  16. Find the value of theta in each of the following: (i)2sin2theta=sqrt(3...

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  17. If A=30^@ verify that cos3A=4cos^3A-3cosA

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  18. If x=30^@ , verify that : (i) tan2x=(2tanx)/(1-tan^2x) (ii) sinx=sqr...

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  19. Verify that: sin60o=(2tan30o)/(1+tan^2 30o)=(sqrt(3))/2 (ii) cos60...

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  20. Verify that: (i) cos60^@=cos^2 30^@-sin^2 30^@=1/2

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