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If a^2+c^2,ab+cd,b^2+d^2 are in continued propotion prove that a,b,c and d are in propotion |
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Answer» Step-by-step explanation: a,B,c and d are in proportion proved below. Step-by-step explanation: (a^2 + c^2), (ab + cd) and (b^2 + d^2)(a 2 +c 2 ),(ab+cd)and(b 2 +d 2 ) are in continued proportion. ⇒ (a^2 + c^2) : (ab + cd) = (ab + cd) : (b^2 + d^2)(a 2 +c 2 ):(ab+cd)=(ab+cd):(b 2 +d 2 ) ⇒ (a^2 + c^2) (b^2 + d^2) = (ab + cd) (ab + cd)(a 2 +c 2 )(b 2 +d 2 )=(ab+cd)(ab+cd) ⇒ a^2b^2 + a^2d^2 + c^2b^2 + c^2d^2 = a^2b^2 + 2abcd + c^2d^2a 2 b 2 +a 2 d 2 +c 2 b 2 +c 2 d 2 =a 2 b 2 +2abcd+c 2 d 2
⇒ a^2d^2 + c^2b^2 -2abcd =0a 2 d 2 +c 2 b 2 −2abcd=0 ⇒ (ad -cb)^2 = 0(ad−cb) 2 =0 [a^2d^2 + c^2b^2 -2abcd=(ad -cb)^2[/tex]] ⇒ ad - c = 0 ⇒ ad = bc ⇒\frac{a}{b} =\frac{c}{d} b a
= d c
⇒ a, b, c and d are in proportion. |
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