please answer.i will definitely mark as BRAINLLIST and thank you
Answers
Question
Prove that:-
1/(3-√8) - 1/(√8 -√7) + 1/(√7-√6) - 1/(√6-√5) + 1/(√5 -2) = 5
Solution
Take L.H.S.
➤ 1/(3-√8) - 1/(√8 -√7) + 1/(√7-√6) - 1/(√6-√5) + 1/(√5 -2)
Rationalize denominators of all term
➤ (3+√8)/(3-√8)(3+√8) - (√8+√7)/(√8+√7)(√8 -√7) + (√7-√6)/(√7-√6)(√7-√6) - (√6+√5)/(√6+√5)(√6-√5) + (√5+2)/(√5+2)(√5 -2)
Using Formula
★ (x²-y²) = (x-y)(x+y)
➤ (3+√8)/{(3)²-(√8)²} - (√8+√7)/{(√8)²-(√7)²} + (√7-√6)/{(√7)²-(√6)²} - (√6+√5)/{(√6)²-(√5)²} + (√5+2)/{(√5)²-(2)²}
➤ (3+√8)/(9-8) - (√8+√7)/(8-7) + (√7-√6)/(7-6) - (√6+√5(/(6-5) + (√5+2)/(5-4)
➤(3+√8) - (√8+√7) + (√7-√6) - (√6+√5) + (√5 + 2)
➤ (3+2)+(√8-√8)+(√7-√7)+(√6-√6)+√5-√5)
➤ 5 + 0 + 0 + 0 + 0
➤ 5
= R.H.S
That's proved.
____________________
Prove that:-
1/(3-√8) - 1/(√8 -√7) + 1/(√7-√6) - 1/(√6-√5) + 1/(√5 -2) = 5
Solution
Take L.H.S.
➤ 1/(3-√8) - 1/(√8 -√7) + 1/(√7-√6) - 1/(√6-√5) + 1/(√5 -2)
Rationalize denominators of all term
➤ (3+√8)/(3-√8)(3+√8) - (√8+√7)/(√8+√7)(√8 -√7) + (√7-√6)/(√7-√6)(√7-√6) - (√6+√5)/(√6+√5)(√6-√5) + (√5+2)/(√5+2)(√5 -2)
Using Formula
★ (x²-y²) = (x-y)(x+y)
➤ (3+√8)/{(3)²-(√8)²} - (√8+√7)/{(√8)²-(√7)²} + (√7-√6)/{(√7)²-(√6)²} - (√6+√5)/{(√6)²-(√5)²} + (√5+2)/{(√5)²-(2)²}
➤ (3+√8)/(9-8) - (√8+√7)/(8-7) + (√7-√6)/(7-6) - (√6+√5(/(6-5) + (√5+2)/(5-4)
➤(3+√8) - (√8+√7) + (√7-√6) - (√6+√5) + (√5 + 2)
➤ (3+2)+(√8-√8)+(√7-√7)+(√6-√6)+√5-√5)
➤ 5 + 0 + 0 + 0 + 0
➤ 5
= R.H.S
That's proved
ʜᴏᴘᴇ ʏᴏᴜ ғɪɴᴅ ɪᴛ ʜᴇʟᴘғᴜʟ
ᴛʜᴀɴᴋ ʏᴏᴜ