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Consider a triangle ABC satisfying ...

Consider a triangle ABC satisfying
`2asin^(2)((C)/(2))+2csin^(2)((A)/(2))=2a+2c-3b`
The sides of the triangle are in

A

G .P

B

A.P

C

H . P

D

Neither in G . P . Nor in A . P nor in H . P

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To solve the problem, we need to analyze the given equation involving the sides of triangle ABC and determine the relationship between these sides. The equation given is: \[ 2a \sin^2\left(\frac{C}{2}\right) + 2c \sin^2\left(\frac{A}{2}\right) = 2a + 2c - 3b \] ### Step 1: Substitute the half-angle sine formulas We know that: \[ \sin\left(\frac{C}{2}\right) = \sqrt{\frac{s-a}{s}} \quad \text{and} \quad \sin\left(\frac{A}{2}\right) = \sqrt{\frac{s-b}{s}} \] where \( s \) is the semi-perimeter of the triangle, given by \( s = \frac{a+b+c}{2} \). Substituting these into the equation gives: \[ 2a \left(\frac{s-a}{s}\right) + 2c \left(\frac{s-b}{s}\right) = 2a + 2c - 3b \] ### Step 2: Simplify the equation Multiply both sides by \( s \) to eliminate the denominator: \[ 2a(s-a) + 2c(s-b) = s(2a + 2c - 3b) \] Expanding both sides: \[ 2as - 2a^2 + 2cs - 2bc = 2as + 2cs - 3bs \] ### Step 3: Rearranging the equation Now, we can rearrange the terms: \[ -2a^2 - 2bc + 3bs = 0 \] ### Step 4: Factor the equation Rearranging gives: \[ 2a^2 + 2bc = 3bs \] This can be rewritten as: \[ 2a^2 = 3bs - 2bc \] ### Step 5: Analyze the relationship Now, we can analyze the relationship between \( a, b, c \). From the equation \( 2a^2 = 3bs - 2bc \), we can derive: \[ a^2 = \frac{3bs - 2bc}{2} \] ### Step 6: Check for arithmetic progression To check if \( a, b, c \) are in arithmetic progression, we need to verify if: \[ b - a = c - b \] This can be rearranged to: \[ a + c = 2b \] ### Conclusion From our derived relationship, we can conclude that: \[ A + C = 2B \] Thus, the sides \( a, b, c \) are in Arithmetic Progression (AP). ### Final Answer The sides of the triangle are in **Arithmetic Progression (AP)**. ---

To solve the problem, we need to analyze the given equation involving the sides of triangle ABC and determine the relationship between these sides. The equation given is: \[ 2a \sin^2\left(\frac{C}{2}\right) + 2c \sin^2\left(\frac{A}{2}\right) = 2a + 2c - 3b \] ### Step 1: Substitute the half-angle sine formulas We know that: \[ \sin\left(\frac{C}{2}\right) = \sqrt{\frac{s-a}{s}} \quad \text{and} \quad \sin\left(\frac{A}{2}\right) = \sqrt{\frac{s-b}{s}} ...
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