Let's 1st understand what these planets represent on their own?

Sun - Sun represents Soul, Personality, King, Government, Father, Authority, Career, Top Positions, Ego, Self Esteem, Health, Education etc.

Jupiter - It is the most benefic planet and it represents all the auspicious things like Knowledge, Wisdom, Law, Guru, Spirituality, Religion, Philosophy, Literature, Elderly People and Children etc. For a girl, Jupiter also represents Husband.

Rahu - It represents Illusion, Foreign Lands, Foreign Things (foreign as in unknown things. So, for someone living in Punjab, culture and rituals of Kerala is also unknown and hence Foreign), Drugs, Medicines, any type of intoxication, Fame, Wealth, Success, Obsession, Past-life incomplete Desires, Movies, Television, Online World, Cheating, Imagined Fears, Unusual Things, Unique Things, Creativity, Rule breaker. Rahu also blows things out of proportions. 

3 planetary conjunction - Whenever 3 or more planets are conjunct with each other in a house/sign then things related to that house/sign become a kind of life focus for person. It is because of huge accumulation of energy within 30 degrees of sky. It means not only these 3 planets' energy is going into this house/sign but the energy of at least 4 to 6 house/sign is going into this house/sign as these planets will be ruling some houses too. So, this house/sign with conjunction becomes almost the most important house in chart. During Career Consultation, I give a huge importance to any such house which has 3 or more planets in it.

House Ruler - Besides these karaka things, Sun, Jupiter & Rahu will also rule some houses in your chart and will represent things related to that house. Of course we can't cover conjunctions Ascendant and house wise else it will never be over. So, you have to include things related to the houses at the time of interpreting this conjunction. Also, we need to keep in mind all Yogas and Raj-Yogas which their conjunction would be making to completely understand the conjunction. Here, we can only cover meaning as per karakas.

Meaning of Sun-Jupiter-Rahu Conjunction - This is another of those conjunctions where person is born during eclipse season and near solar eclipse. The nearer he is born to solar eclipse, the more troubles he can have in his relations with Father, Authority or in finding the right career. Although, Jupiter can be saving grace here from any such confusion. Jupiter can bring wisdom against confusion of Rahu and person can have better idea about Career. But if person is going through Rahu MD in early life then such confusions are inevitable. Jupiter-Rahu together makes sure that person gains loads of knowledge and education during this time which develops his confidence and ego as they are with Sun. More they gain knowledge, more they will be confident in life. At the same time, Jupiter-Rahu conjunction will make Guru-Chandal Yoga activate and they can have weird views on religion and society. They can develop their own society or religion. This person can rebel against usual or ordinary and can gain confidence from such rebellious acts. They can be seen as Teachers or Gurus who are controversial by nature. Overall, this conjunction can make someone gain lots of knowledge but his views can be over the top many a times. 

Who will win the Conjunction? - Rahu is impacting both Jupiter & Sun, so Rahu is winning this conjunction.

Dignity & Strength - 

The basic result of this conjunction will remain as is in any house or sign. House/Sign will change the environment or subject around which these people will educate themselves. Like in Taurus, it can be around wealth, in Scorpio, it can be about Occult & Mysticism, and in Sagittarius, it can be about religious studies etc.