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In DeltaABC, if a = 2, b = 3, c = 4, p...

In `DeltaABC`,
if a = 2, b = 3, c = 4, prove that `cosA=7/8`.

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ICSE-PROPERTIES OF TRIANGLE-EXERCISE 7
  1. In DeltaABC, if a = 2, b = 3, c = 4, prove that cosA=7/8.

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  2. In DeltaABC, if the sides are 7, 4sqrt(3) and sqrt(13) cm, prove tha...

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  3. In DeltaABC, if a = 9, b = 8, c = 4, prove that 6cosC=4+3cosB.

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  4. In DeltaABC, The sines of the angles of a triangle are in the ratio ...

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  5. In DeltaABC, If the two angles of a triangle are 30^(@) and 45^(@) a...

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  6. In DeltaABC, If in a DeltaABC, a = 6, b = 3 and cos(A-B)=4/5, find i...

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  7. In DeltaABC, In a triangle ABC, angleC=60^(@) and angleA=75^(@). If ...

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  8. In any DeltaABC, prove that (sinA)/(sin(A+B))=a/c

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  9. In any DeltaABC, prove that (a-b)/(a+b)=(tan""1/2(A-B))/(tan""1/2(A+...

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  10. In any DeltaABC, prove that ac""cosB-bc""cosA=a^(2)-b^(2)

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  11. In any DeltaABC, prove that (sin(A-B))/(sin(A+B))=(a^(2)-b^(2))/c^(2...

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  12. In any DeltaABC, prove that a(sinB-sinC)+b(sinC-sinA)+c(sinA-sinB)=0

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  13. In any DeltaABC, prove that acos(A+B+C)-bcos(B+A)-c""cos(A+C)=0

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  14. In any DeltaABC, prove that a(cosC-cosB)=2(b-c)cos^(2)""1/2A

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  15. In any DeltaABC, prove that asin""1/2(B-C)=(b-c)cos""1/2A

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  16. In any DeltaABC, prove that asin(A/2+B)=(b+c)sin""A/2

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  17. In any DeltaABC, prove that c^(2)=(a-b)^(2)cos^(2)""1/2C+(a+b)^(2)si...

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  18. In any DeltaABC, prove that asin(B-C)+bsin(C-A)+csin(A-B)=0

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  19. In any DeltaABC, prove that (cos2A)/a^(2)-(cos2B)/b^(2)=1/a^(2)-1/b^...

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  20. In any DeltaABC, prove that (1+cos(A-B)cosC)/(1+cos(A-C)cosB)=(a^(2)...

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